diff --git a/nw/__init__.py b/nw/__init__.py
index 02ac7162..8cb87d08 100644
--- a/nw/__init__.py
+++ b/nw/__init__.py
@@ -32,7 +32,7 @@ import logging
 from PyQt5.QtGui import QIcon
 from PyQt5.QtWidgets import QApplication, QErrorMessage
 
-from nw.error import exceptionHandler
+from nw.error import exceptionHandler, logException
 from nw.config import Config
 
 ##
@@ -268,9 +268,9 @@ def main(sysArgs=None):
             bundle = NSBundle.mainBundle()
             info = bundle.localizedInfoDictionary() or bundle.infoDictionary()
             info["CFBundleName"] = "novelWriter"
-        except ImportError as e:
+        except ImportError:
             logger.error("Failed to set application name")
-            logger.error(str(e))
+            logException()
 
     # Import GUI (after dependency checks), and launch
     from nw.guimain import GuiMain
diff --git a/nw/common.py b/nw/common.py
index 11546c88..826f7370 100644
--- a/nw/common.py
+++ b/nw/common.py
@@ -30,7 +30,9 @@ from datetime import datetime
 
 from PyQt5.QtWidgets import qApp
 
-from nw.constants import nwConst, nwUnicode
+from nw.constants import (
+    nwConst, nwUnicode, nwItemClass, nwItemType, nwItemLayout
+)
 
 logger = logging.getLogger(__name__)
 
@@ -103,11 +105,39 @@ def isHandle(theString):
         return False
     if len(theString) != 13:
         return False
-    invalidChar = False
     for c in theString:
         if c not in "0123456789abcdef":
-            invalidChar = True
-    return not invalidChar
+            return False
+    return True
+
+def isTitleTag(theString):
+    """Check if a string is a valid title string.
+    """
+    if not isinstance(theString, str):
+        return False
+    if len(theString) != 7:
+        return False
+    if not theString.startswith("T"):
+        return False
+    for c in theString[1:]:
+        if c not in "0123456789":
+            return False
+    return True
+
+def isItemClass(theString):
+    """Check if an item is a calid nwItemClass identifier.
+    """
+    return theString in nwItemClass.__members__
+
+def isItemType(theString):
+    """Check if an item is a calid nwItemType identifier.
+    """
+    return theString in nwItemType.__members__
+
+def isItemLayout(theString):
+    """Check if an item is a calid nwItemLayout identifier.
+    """
+    return theString in nwItemLayout.__members__
 
 def hexToInt(value, default=0):
     """Convert a hex string to an integer.
diff --git a/nw/config.py b/nw/config.py
index d35582fb..1a9aade2 100644
--- a/nw/config.py
+++ b/nw/config.py
@@ -38,6 +38,7 @@ from PyQt5.QtCore import QT_VERSION_STR, QStandardPaths, QSysInfo
 
 from nw.constants import nwConst, nwFiles, nwUnicode
 from nw.common import splitVersionNumber, formatTimeStamp
+from nw.error import logException
 
 logger = logging.getLogger(__name__)
 
@@ -293,7 +294,7 @@ class Config:
                 os.mkdir(self.confPath)
             except Exception as e:
                 logger.error("Could not create folder: %s" % self.confPath)
-                logger.error(str(e))
+                logException()
                 self.hasError = True
                 self.errData.append("Could not create folder: %s" % self.confPath)
                 self.errData.append(str(e))
@@ -316,7 +317,7 @@ class Config:
                     os.mkdir(self.dataPath)
                 except Exception as e:
                     logger.error("Could not create folder: %s" % self.dataPath)
-                    logger.error(str(e))
+                    logException()
                     self.hasError = True
                     self.errData.append("Could not create folder: %s" % self.dataPath)
                     self.errData.append(str(e))
@@ -361,7 +362,7 @@ class Config:
                 cnfParse.read_file(inFile)
         except Exception as e:
             logger.error("Could not load config file")
-            logger.error(str(e))
+            logException()
             self.hasError = True
             self.errData.append("Could not load config file")
             self.errData.append(str(e))
@@ -702,7 +703,7 @@ class Config:
             self.confChanged = False
         except Exception as e:
             logger.error("Could not save config file")
-            logger.error(str(e))
+            logException()
             self.hasError = True
             self.errData.append("Could not save config file")
             self.errData.append(str(e))
@@ -978,9 +979,9 @@ class Config:
                         return self._unpackList(
                             cnfParse.get(cnfSec, cnfName), cnfDefault, self.CNF_S_LST
                         )
-                except ValueError as e:
+                except ValueError:
                     logger.error("Failed to load value from config file.")
-                    logger.error(str(e))
+                    logException()
                     return cnfDefault
 
         return cnfDefault
diff --git a/nw/core/index.py b/nw/core/index.py
index ba2e06f3..7a9c88bc 100644
--- a/nw/core/index.py
+++ b/nw/core/index.py
@@ -36,11 +36,13 @@ from nw.constants import (
 )
 from nw.core.document import NWDoc
 from nw.core.tools import countWords
+from nw.common import isHandle, isTitleTag, isItemClass, isItemLayout
 
 logger = logging.getLogger(__name__)
 
 class NWIndex():
 
+    H_VALID = ("H0", "H1", "H2", "H3", "H4")
     H_LEVEL = {"H0": 0, "H1": 1, "H2": 2, "H3": 3, "H4": 4}
 
     def __init__(self, theProject, theParent):
@@ -152,9 +154,14 @@ class NWIndex():
             try:
                 with open(indexFile, mode="r", encoding="utf8") as inFile:
                     theData = json.load(inFile)
-            except Exception as e:
+            except Exception:
                 logger.error("Failed to load index file")
-                logger.error(str(e))
+                nw.logException()
+                self.indexBroken = True
+                self.theParent.makeAlert(
+                    "Could not load cached index file. Rebuilding index.",
+                    nwAlert.WARN
+                )
                 return False
 
             self._tagIndex   = theData.get("tagIndex", {})
@@ -188,9 +195,9 @@ class NWIndex():
                     "noteIndex"  : self._noteIndex,
                     "textCounts" : self._textCounts,
                 }, outFile, indent=2)
-        except Exception as e:
+        except Exception:
             logger.error("Failed to save index file")
-            logger.error(str(e))
+            nw.logException()
             return False
 
         return True
@@ -200,37 +207,25 @@ class NWIndex():
         elements it should.
         """
         logger.debug("Checking index")
-        self.indexBroken = False
+        tStart = time()
 
         try:
-            for tTag in self._tagIndex:
-                if len(self._tagIndex[tTag]) != 4:
-                    self.indexBroken = True
-
-            for tHandle in self._refIndex:
-                for sTitle in self._refIndex[tHandle]:
-                    for tEntry in self._refIndex[tHandle][sTitle]["tags"]:
-                        if len(tEntry) != 3:
-                            self.indexBroken = True
-
-            for tHandle in self._novelIndex:
-                for sLine in self._novelIndex[tHandle]:
-                    if len(self._novelIndex[tHandle][sLine].keys()) != 8:
-                        self.indexBroken = True
-
-            for tHandle in self._noteIndex:
-                for sLine in self._noteIndex[tHandle]:
-                    if len(self._noteIndex[tHandle][sLine].keys()) != 8:
-                        self.indexBroken = True
-
-            for tHandle in self._textCounts:
-                if len(self._textCounts[tHandle]) != 3:
-                    self.indexBroken = True
+            self._checkTagIndex()
+            self._checkRefIndex()
+            self._checkNovelNoteIndex("novelIndex")
+            self._checkNovelNoteIndex("noteIndex")
+            self._checkTextCounts()
+            self.indexBroken = False
 
         except Exception:
+            logger.error("Error while checking index")
+            nw.logException()
             self.indexBroken = True
 
+        tEnd = time()
+        logger.debug("Index check took %.3f ms" % ((tEnd - tStart)*1000))
         logger.debug("Index check complete")
+
         if self.indexBroken:
             self.clearIndex()
             self.theParent.makeAlert(
@@ -745,4 +740,143 @@ class NWIndex():
 
         return theHandles
 
+    ##
+    #  Index Checkers
+    ##
+
+    def _checkTagIndex(self):
+        """Scan the tag index for errors.
+        Waring: This function raises exceptions.
+        """
+        for tTag in self._tagIndex:
+            if not isinstance(tTag, str):
+                raise KeyError("tagIndex key is not a string")
+
+            tEntry = self._tagIndex[tTag]
+            if len(tEntry) != 4:
+                raise IndexError("tagIndex[a] expected 4 values")
+            if not isinstance(tEntry[0], int):
+                raise ValueError("tagIndex[a][0] is not an integer")
+            if not isHandle(tEntry[1]):
+                raise ValueError("tagIndex[a][1] is not a handle")
+            if not isItemClass(tEntry[2]):
+                raise ValueError("tagIndex[a][2] is not an nwItemClass")
+            if not isTitleTag(tEntry[3]):
+                raise ValueError("tagIndex[a][3] is not a title tag")
+
+        return
+
+    def _checkRefIndex(self):
+        """Scan the reference index for errors.
+        Waring: This function raises exceptions.
+        """
+        for tHandle in self._refIndex:
+            if not isHandle(tHandle):
+                raise KeyError("refIndex key is not a handle")
+
+            hEntry = self._refIndex[tHandle]
+            for sTitle in hEntry:
+                if not isTitleTag(sTitle):
+                    raise KeyError("refIndex[a] key is not a title tag")
+
+                sEntry = hEntry[sTitle]
+                if "tags" not in sEntry:
+                    raise KeyError("refIndex[a][b] has no 'tag' key")
+                for tEntry in sEntry["tags"]:
+                    if len(tEntry) != 3:
+                        raise IndexError("refIndex[a][b][tags][i] expected 3 values")
+                    if not isinstance(tEntry[0], int):
+                        raise ValueError("refIndex[a][b][tags][i][0] is not an integer")
+                    if not tEntry[1] in nwKeyWords.VALID_KEYS:
+                        raise ValueError("refIndex[a][b][tags][i][1] is not a keyword")
+                    if not isinstance(tEntry[2], str):
+                        raise ValueError("refIndex[a][b][tags][i][2] is not a string")
+
+                if "updated" not in sEntry:
+                    raise KeyError("refIndex[a][b] has no 'updated' key")
+                if not isinstance(sEntry["updated"], int):
+                    raise ValueError("%refIndex[a][b][updated] is not an integer")
+
+        return
+
+    def _checkNovelNoteIndex(self, idxName):
+        """Scan the novel or note index for errors.
+        Waring: This function raises exceptions.
+        """
+        if idxName == "novelIndex":
+            theIndex = self._novelIndex
+        elif idxName == "noteIndex":
+            theIndex = self._noteIndex
+        else:
+            raise IndexError("Unknown index %s" % idxName)
+
+        for tHandle in theIndex:
+            if not isHandle(tHandle):
+                raise KeyError("%s key is not a handle" % idxName)
+
+            hEntry = theIndex[tHandle]
+            for sTitle in theIndex[tHandle]:
+                if not isTitleTag(sTitle):
+                    raise KeyError("%s[a] key is not a title tag" % idxName)
+
+                sEntry = hEntry[sTitle]
+                if len(sEntry) != 8:
+                    raise IndexError("%s[a][b] expected 8 values" % idxName)
+
+                if "level" not in sEntry:
+                    raise KeyError("%s[a][b] has no 'level' key" % idxName)
+                if "title" not in sEntry:
+                    raise KeyError("%s[a][b] has no 'title' key" % idxName)
+                if "layout" not in sEntry:
+                    raise KeyError("%s[a][b] has no 'layout' key" % idxName)
+                if "synopsis" not in sEntry:
+                    raise KeyError("%s[a][b] has no 'synopsis' key" % idxName)
+                if "cCount" not in sEntry:
+                    raise KeyError("%s[a][b] has no 'cCount' key" % idxName)
+                if "wCount" not in sEntry:
+                    raise KeyError("%s[a][b] has no 'wCount' key" % idxName)
+                if "pCount" not in sEntry:
+                    raise KeyError("%s[a][b] has no 'pCount' key" % idxName)
+                if "updated" not in sEntry:
+                    raise KeyError("%s[a][b] has no 'updated' key" % idxName)
+
+                if not sEntry["level"] in self.H_VALID:
+                    raise ValueError("%s[a][b][level] is not a header level" % idxName)
+                if not isinstance(sEntry["title"], str):
+                    raise ValueError("%s[a][b][title] is not a string" % idxName)
+                if not isItemLayout(sEntry["layout"]):
+                    raise ValueError("%s[a][b][layout] is not an nwItemLayout" % idxName)
+                if not isinstance(sEntry["synopsis"], str):
+                    raise ValueError("%s[a][b][synopsis] is not a string" % idxName)
+                if not isinstance(sEntry["cCount"], int):
+                    raise ValueError("%s[a][b][cCount] is not an integer" % idxName)
+                if not isinstance(sEntry["wCount"], int):
+                    raise ValueError("%s[a][b][wCount] is not an integer" % idxName)
+                if not isinstance(sEntry["pCount"], int):
+                    raise ValueError("%s[a][b][pCount] is not an integer" % idxName)
+                if not isinstance(sEntry["updated"], int):
+                    raise ValueError("%s[a][b][updated] is not an integer" % idxName)
+
+        return
+
+    def _checkTextCounts(self):
+        """Scan the text counts index for errors.
+        Waring: This function raises exceptions.
+        """
+        for tHandle in self._textCounts:
+            if not isHandle(tHandle):
+                raise KeyError("textCounts key is not a handle")
+
+            tEntry = self._textCounts[tHandle]
+            if len(tEntry) != 3:
+                raise IndexError("textCounts[a] expected 3 values")
+            if not isinstance(tEntry[0], int):
+                raise ValueError("textCounts[a][0] is not an integer")
+            if not isinstance(tEntry[1], int):
+                raise ValueError("textCounts[a][1] is not an integer")
+            if not isinstance(tEntry[2], int):
+                raise ValueError("textCounts[a][2] is not an integer")
+
+        return
+
 # END Class NWIndex
diff --git a/nw/core/item.py b/nw/core/item.py
index e2a5a4e8..62460e7e 100644
--- a/nw/core/item.py
+++ b/nw/core/item.py
@@ -28,8 +28,10 @@ import logging
 
 from lxml import etree
 
-from nw.common import checkInt, isHandle
 from nw.constants import nwItemType, nwItemClass, nwItemLayout
+from nw.common import (
+    checkInt, isHandle, isItemClass, isItemLayout, isItemType
+)
 
 logger = logging.getLogger(__name__)
 
@@ -201,7 +203,7 @@ class NWItem():
         """
         if isinstance(theType, nwItemType):
             self.itemType = theType
-        elif theType in nwItemType.__members__:
+        elif isItemType(theType):
             self.itemType = nwItemType[theType]
         else:
             logger.error("Unrecognised item type '%s'" % theType)
@@ -214,7 +216,7 @@ class NWItem():
         """
         if isinstance(theClass, nwItemClass):
             self.itemClass = theClass
-        elif theClass in nwItemClass.__members__:
+        elif isItemClass(theClass):
             self.itemClass = nwItemClass[theClass]
         else:
             logger.error("Unrecognised item class '%s'" % theClass)
@@ -227,7 +229,7 @@ class NWItem():
         """
         if isinstance(theLayout, nwItemLayout):
             self.itemLayout = theLayout
-        elif theLayout in nwItemLayout.__members__:
+        elif isItemLayout(theLayout):
             self.itemLayout = nwItemLayout[theLayout]
         else:
             logger.error("Unrecognised item layout '%s'" % theLayout)
diff --git a/nw/core/options.py b/nw/core/options.py
index 36da3f32..c0df1855 100644
--- a/nw/core/options.py
+++ b/nw/core/options.py
@@ -25,6 +25,7 @@ You should have received a copy of the GNU General Public License
 along with this program. If not, see <https://www.gnu.org/licenses/>.
 """
 
+import nw
 import logging
 import json
 import os
@@ -121,9 +122,9 @@ class OptionState():
             try:
                 with open(stateFile, mode="r", encoding="utf8") as inFile:
                     theState = json.load(inFile)
-            except Exception as e:
+            except Exception:
                 logger.error("Failed to load GUI options file")
-                logger.error(str(e))
+                nw.logException()
                 return False
 
         # Filter out unused variables
@@ -148,9 +149,9 @@ class OptionState():
         try:
             with open(stateFile, mode="w+", encoding="utf8") as outFile:
                 json.dump(self.theState, outFile, indent=2)
-        except Exception as e:
+        except Exception:
             logger.error("Failed to save GUI options file")
-            logger.error(str(e))
+            nw.logException()
             return False
 
         return True
diff --git a/nw/core/project.py b/nw/core/project.py
index a22f7aa9..90d3649f 100644
--- a/nw/core/project.py
+++ b/nw/core/project.py
@@ -1219,9 +1219,9 @@ class NWProject():
                 if len(theLines) != 4:
                     return ["ERROR"]
 
-        except Exception as e:
+        except Exception:
             logger.error("Failed to read project lockfile")
-            logger.error(str(e))
+            nw.logException()
             return ["ERROR"]
 
         return theLines
@@ -1240,9 +1240,9 @@ class NWProject():
                 outFile.write("%s\n" % self.mainConf.kernelVer)
                 outFile.write("%d\n" % time())
 
-        except Exception as e:
+        except Exception:
             logger.error("Failed to write project lockfile")
-            logger.error(str(e))
+            nw.logException()
             return False
 
         return True
@@ -1257,9 +1257,9 @@ class NWProject():
         if os.path.isfile(lockFile):
             try:
                 os.unlink(lockFile)
-            except Exception as e:
+            except Exception:
                 logger.error("Failed to remove project lockfile")
-                logger.error(str(e))
+                nw.logException()
                 return False
 
         return True
@@ -1415,9 +1415,9 @@ class NWProject():
                     self.notesWCount,
                 ))
 
-        except Exception as e:
+        except Exception:
             logger.error("Failed to write session stats file")
-            logger.error(str(e))
+            nw.logException()
             return False
 
         return True
@@ -1453,17 +1453,19 @@ class NWProject():
                     os.rename(theFile, newPath)
                     logger.info("Moved file: %s" % theFile)
                     logger.info("New location: %s" % newPath)
-                except Exception as e:
-                    logger.error(str(e))
+                except Exception:
                     errList.append("Could not move: %s" % theFile)
+                    logger.error("Could not move: %s" % theFile)
+                    nw.logException()
 
             elif len(dataItem) == 21 and dataItem.endswith("_main.bak"):
                 try:
                     os.unlink(theFile)
                     logger.info("Deleted file: %s" % theFile)
-                except Exception as e:
-                    logger.error(str(e))
+                except Exception:
                     errList.append("Could not delete: %s" % theFile)
+                    logger.error("Could not delete: %s" % theFile)
+                    nw.logException()
 
             else:
                 theErr = self._moveUnknownItem(theData, dataItem)
@@ -1475,9 +1477,10 @@ class NWProject():
         try:
             os.rmdir(theData)
             logger.info("Removed folder: %s" % theFolder)
-        except Exception as e:
-            logger.error(str(e))
+        except Exception:
             errList.append("Failed to remove: %s" % theFolder)
+            logger.error("Failed to remove: %s" % theFolder)
+            nw.logException()
 
         return errList
 
@@ -1495,8 +1498,9 @@ class NWProject():
         try:
             os.rename(theSrc, theDst)
             logger.info("Moved to junk: %s" % theSrc)
-        except Exception as e:
-            logger.error(str(e))
+        except Exception:
+            logger.error("Could not move item %s to junk." % theSrc)
+            nw.logException()
             return "Could not move item %s to junk." % theSrc
 
         return ""
@@ -1529,8 +1533,9 @@ class NWProject():
                 logger.info("Deleting: %s" % rmFile)
                 try:
                     os.unlink(rmFile)
-                except Exception as e:
-                    logger.error(str(e))
+                except Exception:
+                    logger.error("Could not delete: %s" % rmFile)
+                    nw.logException()
                     return False
 
         return True
diff --git a/nw/core/spellcheck.py b/nw/core/spellcheck.py
index 8b3807fa..8dd33bbe 100644
--- a/nw/core/spellcheck.py
+++ b/nw/core/spellcheck.py
@@ -72,9 +72,9 @@ class NWSpellCheck():
                 with open(self.projectDict, mode="a+", encoding="utf-8") as outFile:
                     outFile.write("%s\n" % newWord)
                 self.projDict.append(newWord)
-            except Exception as e:
+            except Exception:
                 logger.error("Failed to add word to project word list %s" % str(self.projectDict))
-                logger.error(str(e))
+                nw.logException()
                 return False
             return True
         return False
@@ -123,9 +123,9 @@ class NWSpellCheck():
                         if len(theLine) > 0 and theLine not in self.projDict:
                             self.projDict.append(theLine)
                 logger.debug("Project word list contains %d words" % len(self.projDict))
-            except Exception as e:
+            except Exception:
                 logger.error("Failed to load project word list")
-                logger.error(str(e))
+                nw.logException()
                 return False
 
         return True
@@ -201,9 +201,9 @@ class NWSpellEnchant(NWSpellCheck):
         try:
             spTag = self.theDict.tag
             spName = self.theDict.provider.name
-        except Exception as e:
+        except Exception:
             logger.error("Failed to extract information about the dictionary")
-            logger.error(str(e))
+            nw.logException()
             spTag = ""
             spName = ""
 
@@ -261,9 +261,9 @@ class NWSpellSimple(NWSpellCheck):
             logger.debug("Spell check word list for language %s loaded" % theLang)
             logger.debug("Word list contains %d words" % len(self.WORDS))
             self.spellLanguage = theLang
-        except Exception as e:
+        except Exception:
             logger.error("Failed to load spell check word list for language %s" % theLang)
-            logger.error(str(e))
+            nw.logException()
             self.spellLanguage = None
 
         self._readProjectDictionary(projectDict)
diff --git a/nw/core/tree.py b/nw/core/tree.py
index 36a56e5c..94e9b97a 100644
--- a/nw/core/tree.py
+++ b/nw/core/tree.py
@@ -24,6 +24,7 @@ You should have received a copy of the GNU General Public License
 along with this program. If not, see <https://www.gnu.org/licenses/>.
 """
 
+import nw
 import logging
 import os
 
@@ -179,8 +180,9 @@ class NWTree():
                 outFile.write("\n".join(tocList))
                 outFile.write("\n")
 
-        except Exception as e:
-            logger.error(str(e))
+        except Exception:
+            logger.error("Could not write ToC file")
+            nw.logException()
             return False
 
         return True
diff --git a/nw/error.py b/nw/error.py
index 1f879e37..998b7347 100644
--- a/nw/error.py
+++ b/nw/error.py
@@ -24,12 +24,31 @@ You should have received a copy of the GNU General Public License
 along with this program. If not, see <https://www.gnu.org/licenses/>.
 """
 
+import sys
+import logging
+
 from PyQt5.QtCore import Qt
 from PyQt5.QtWidgets import (
     qApp, QDialog, QGridLayout, QStyle, QPlainTextEdit, QLabel,
     QDialogButtonBox
 )
 
+logger = logging.getLogger(__name__)
+
+# =============================================================================================== #
+#  Utility Functions
+# =============================================================================================== #
+
+def logException():
+    """Log the content of an exception message.
+    """
+    exType, exValue, _ = sys.exc_info()
+    logger.error("%s: %s" % (exType.__name__, str(exValue).strip("'")))
+
+# =============================================================================================== #
+#  Error Handler
+# =============================================================================================== #
+
 class NWErrorMessage(QDialog):
 
     def __init__(self, parent):
@@ -72,7 +91,6 @@ class NWErrorMessage(QDialog):
         """Generate a message and append session data, error info and
         error traceback.
         """
-        import sys
         from traceback import format_tb
         from nw import __issuesurl__, __version__
         from PyQt5.Qt import PYQT_VERSION_STR
@@ -133,15 +151,12 @@ class NWErrorMessage(QDialog):
 
 # END Class NWErrorMessage
 
-
 def exceptionHandler(exType, exValue, exTrace):
     """Function to catch unhandled global exceptions.
     """
-    import logging
     from traceback import print_tb
     from PyQt5.QtWidgets import qApp
 
-    logger = logging.getLogger(__name__)
     logger.critical("%s: %s" % (exType.__name__, str(exValue)))
     print_tb(exTrace)
 
diff --git a/nw/gui/build.py b/nw/gui/build.py
index 5bcea455..18bb4dc7 100644
--- a/nw/gui/build.py
+++ b/nw/gui/build.py
@@ -671,9 +671,9 @@ class GuiBuildNovel(QDialog):
                         bldObj.doConvert()
                     bldObj.doPostProcessing()
 
-            except Exception as e:
+            except Exception:
                 logger.error("Failed to generate html of document '%s'" % tItem.itemHandle)
-                logger.error(str(e))
+                nw.logException()
                 if isPreview:
                     self.docView.setText((
                         "Failed to generate preview. "
@@ -997,9 +997,9 @@ class GuiBuildNovel(QDialog):
                 with open(buildCache, mode="r", encoding="utf8") as inFile:
                     theJson = inFile.read()
                 theData = json.loads(theJson)
-            except Exception as e:
+            except Exception:
                 logger.error("Failed to load build cache")
-                logger.error(str(e))
+                nw.logException()
                 return False
 
             if "htmlText" in theData.keys():
@@ -1026,9 +1026,9 @@ class GuiBuildNovel(QDialog):
                     "htmlStyle" : self.htmlStyle,
                     "buildTime" : self.buildTime,
                 }, indent=2))
-        except Exception as e:
+        except Exception:
             logger.error("Failed to save build cache")
-            logger.error(str(e))
+            nw.logException()
             return False
 
         return True
diff --git a/nw/gui/docviewer.py b/nw/gui/docviewer.py
index 55e458bb..24d53019 100644
--- a/nw/gui/docviewer.py
+++ b/nw/gui/docviewer.py
@@ -180,9 +180,9 @@ class GuiDocViewer(QTextBrowser):
             aDoc.tokenizeText()
             aDoc.doConvert()
             aDoc.doPostProcessing()
-        except Exception as e:
+        except Exception:
             logger.error("Failed to generate preview for document with handle '%s'" % tHandle)
-            logger.error(str(e))
+            nw.logException()
             self.setText("An error occurred while generating the preview.")
             return False
 
diff --git a/nw/gui/theme.py b/nw/gui/theme.py
index 8aa0c1fe..73d8a7b0 100644
--- a/nw/gui/theme.py
+++ b/nw/gui/theme.py
@@ -265,9 +265,9 @@ class GuiTheme:
             if os.path.isfile(self.cssFile):
                 with open(self.cssFile, mode="r", encoding="utf8") as inFile:
                     cssData = inFile.read()
-        except Exception as e:
+        except Exception:
             logger.error("Could not load theme css file")
-            logger.error(str(e))
+            nw.logException()
             return False
 
         # Config File
@@ -275,9 +275,9 @@ class GuiTheme:
         try:
             with open(self.confFile, mode="r", encoding="utf8") as inFile:
                 confParser.read_file(inFile)
-        except Exception as e:
+        except Exception:
             logger.error("Could not load theme settings from: %s" % self.confFile)
-            logger.error(str(e))
+            nw.logException()
             return False
 
         ## Main
@@ -333,9 +333,9 @@ class GuiTheme:
         try:
             with open(self.syntaxFile, mode="r", encoding="utf8") as inFile:
                 confParser.read_file(inFile)
-        except Exception as e:
+        except Exception:
             logger.error("Could not load syntax colours from: %s" % self.syntaxFile)
-            logger.error(str(e))
+            nw.logException()
             return False
 
         ## Main
@@ -637,9 +637,9 @@ class GuiIcons:
         try:
             with open(self.confFile, mode="r", encoding="utf8") as inFile:
                 confParser.read_file(inFile)
-        except Exception as e:
+        except Exception:
             logger.error("Could not load icon theme settings from: %s" % self.confFile)
-            logger.error(str(e))
+            nw.logException()
             return False
 
         ## Main
diff --git a/tests/test_base/test_base_common.py b/tests/test_base/test_base_common.py
index 79b6562a..4b076a64 100644
--- a/tests/test_base/test_base_common.py
+++ b/tests/test_base/test_base_common.py
@@ -26,7 +26,8 @@ import pytest
 from nw.common import (
     checkString, checkBool, checkInt, colRange, formatInt, transferCase,
     fuzzyTime, checkHandle, formatTimeStamp, formatTime, hexToInt,
-    makeFileNameSafe
+    makeFileNameSafe, isHandle, isTitleTag, isItemClass, isItemType,
+    isItemLayout
 )
 from tools import cmpList
 
@@ -88,6 +89,95 @@ def testBaseCommon_CheckHandle():
 
 # END Test testBaseCommon_CheckHandle
 
+@pytest.mark.base
+def testBaseCommon_IsHandle():
+    """Test the isHandle function.
+    """
+    assert isHandle("47666c91c7ccf")
+
+    assert not isHandle("47666C91C7CCF")
+    assert not isHandle("h7666c91c7ccf")
+    assert not isHandle("None")
+    assert not isHandle(None)
+    assert not isHandle("STUFF")
+
+# END Test testBaseCommon_IsHandle
+
+@pytest.mark.base
+def testBaseCommon_IsTitleTag():
+    """Test the isItemClass function.
+    """
+    assert isTitleTag("T123456")
+
+    assert not isTitleTag("t123456")
+    assert not isTitleTag("S123456")
+    assert not isTitleTag("T12345A")
+    assert not isTitleTag("T1234567")
+
+    assert not isTitleTag("None")
+    assert not isTitleTag(None)
+    assert not isTitleTag("STUFF")
+
+# END Test testBaseCommon_IsTitleTag
+
+@pytest.mark.base
+def testBaseCommon_IsItemClass():
+    """Test the isItemClass function.
+    """
+    assert isItemClass("NO_CLASS")
+    assert isItemClass("NOVEL")
+    assert isItemClass("PLOT")
+    assert isItemClass("CHARACTER")
+    assert isItemClass("WORLD")
+    assert isItemClass("TIMELINE")
+    assert isItemClass("OBJECT")
+    assert isItemClass("ENTITY")
+    assert isItemClass("CUSTOM")
+    assert isItemClass("ARCHIVE")
+    assert isItemClass("TRASH")
+
+    assert not isItemClass("None")
+    assert not isItemClass(None)
+    assert not isItemClass("STUFF")
+
+# END Test testBaseCommon_IsItemClass
+
+@pytest.mark.base
+def testBaseCommon_IsItemType():
+    """Test the isItemType function.
+    """
+    assert isItemType("NO_TYPE")
+    assert isItemType("ROOT")
+    assert isItemType("FOLDER")
+    assert isItemType("FILE")
+    assert isItemType("TRASH")
+
+    assert not isItemType("None")
+    assert not isItemType(None)
+    assert not isItemType("STUFF")
+
+# END Test testBaseCommon_IsItemType
+
+@pytest.mark.base
+def testBaseCommon_IsItemLayout():
+    """Test the isItemLayout function.
+    """
+    assert isItemLayout("NO_LAYOUT")
+    assert isItemLayout("TITLE")
+    assert isItemLayout("BOOK")
+    assert isItemLayout("PAGE")
+    assert isItemLayout("PARTITION")
+    assert isItemLayout("UNNUMBERED")
+    assert isItemLayout("CHAPTER")
+    assert isItemLayout("SCENE")
+    assert isItemLayout("NOTE")
+
+    assert not isItemLayout("None")
+    assert not isItemLayout(None)
+    assert not isItemLayout("STUFF")
+
+# END Test testBaseCommon_IsItemLayout
+
 @pytest.mark.base
 def testBaseCommon_HexToInt():
     """Test the hexToInt function.
diff --git a/tests/test_core/test_core_index.py b/tests/test_core/test_core_index.py
index e10000d6..5e1e9223 100644
--- a/tests/test_core/test_core_index.py
+++ b/tests/test_core/test_core_index.py
@@ -115,38 +115,7 @@ def testCoreIndex_LoadSave(monkeypatch, nwLipsum, dummyGUI, outDir, refDir):
 
     # Break the index and check that we notice
     assert not theIndex.indexBroken
-    theIndex._tagIndex["Bod"].append("Stuff") # No longer len() == 4
-    theIndex.checkIndex()
-    assert theIndex.indexBroken
-
-    assert theIndex.loadIndex()
-    assert not theIndex.indexBroken
-    theIndex._refIndex["fb609cd8319dc"]["T000001"]["tags"].append("Stuff") # No longer len() == 3
-    theIndex.checkIndex()
-    assert theIndex.indexBroken
-
-    assert theIndex.loadIndex()
-    assert not theIndex.indexBroken
-    theIndex._novelIndex["7a992350f3eb6"]["T000001"]["Stuff"] = "" # No longer len(keys()) == 8
-    theIndex.checkIndex()
-    assert theIndex.indexBroken
-
-    assert theIndex.loadIndex()
-    assert not theIndex.indexBroken
-    theIndex._noteIndex["4c4f28287af27"]["T000001"]["Stuff"] = "" # No longer len(keys()) == 8
-    theIndex.checkIndex()
-    assert theIndex.indexBroken
-
-    assert theIndex.loadIndex()
-    assert not theIndex.indexBroken
-    theIndex._textCounts["7a992350f3eb6"].append("Stuff") # No longer len() == 3
-    theIndex.checkIndex()
-    assert theIndex.indexBroken
-
-    # Make the try/except trigger as well
-    assert theIndex.loadIndex()
-    assert not theIndex.indexBroken
-    theIndex._refIndex["fb609cd8319dc"]["T000001"] = {"tagssss": []} # Wrong key name
+    theIndex._tagIndex["Bod"].append("Stuff")
     theIndex.checkIndex()
     assert theIndex.indexBroken
 
@@ -676,3 +645,503 @@ def testCoreIndex_ExtractData(nwMinimal, dummyGUI):
     assert theProject.closeProject()
 
 # END Test testCoreIndex_ExtractData
+
+@pytest.mark.core
+def testCoreIndex_CheckTagIndex(dummyGUI):
+    """Test the tag index checker.
+    """
+    theProject = NWProject(dummyGUI)
+    theIndex = NWIndex(theProject, dummyGUI)
+
+    # Valid Index
+    theIndex._tagIndex = {
+        "John": [3, "14298de4d9524", "CHARACTER", "T000001"],
+        "Jane": [3, "bb2c23b3c42cc", "CHARACTER", "T000001"],
+    }
+    assert theIndex._checkTagIndex() is None
+
+    # Wrong Key Type
+    theIndex._tagIndex = {
+        "John": [3, "14298de4d9524", "CHARACTER", "T000001"],
+        123456: [3, "bb2c23b3c42cc", "CHARACTER", "T000001"],
+    }
+    with pytest.raises(KeyError):
+        theIndex._checkTagIndex()
+
+    # Wrong Length
+    theIndex._tagIndex = {
+        "John": [3, "14298de4d9524", "CHARACTER", "T000001"],
+        "Jane": [3, "bb2c23b3c42cc", "CHARACTER", "T000001", "Stuff"],
+    }
+    with pytest.raises(IndexError):
+        theIndex._checkTagIndex()
+
+    # Wrong Type of Entry 0
+    theIndex._tagIndex = {
+        "John": [3, "14298de4d9524", "CHARACTER", "T000001"],
+        "Jane": ["3", "bb2c23b3c42cc", "CHARACTER", "T000001"],
+    }
+    with pytest.raises(ValueError):
+        theIndex._checkTagIndex()
+
+    # Wrong Type of Entry 1
+    theIndex._tagIndex = {
+        "John": [3, "14298de4d9524", "CHARACTER", "T000001"],
+        "Jane": [3, 0xbb2c23b3c42cc, "CHARACTER", "T000001"],
+    }
+    with pytest.raises(ValueError):
+        theIndex._checkTagIndex()
+
+    # Wrong Type of Entry 2
+    theIndex._tagIndex = {
+        "John": [3, "14298de4d9524", "CHARACTER", "T000001"],
+        "Jane": [3, "bb2c23b3c42cc", "INVALID_CLASS", "T000001"],
+    }
+    with pytest.raises(ValueError):
+        theIndex._checkTagIndex()
+
+    # Wrong Type of Entry 3
+    theIndex._tagIndex = {
+        "John": [3, "14298de4d9524", "CHARACTER", "T000001"],
+        "Jane": [3, "bb2c23b3c42cc", "CHARACTER", "INVALID"],
+    }
+    with pytest.raises(ValueError):
+        theIndex._checkTagIndex()
+
+# END Test testCoreIndex_CheckTagIndex
+
+@pytest.mark.core
+def testCoreIndex_CheckRefIndex(dummyGUI):
+    """Test the reference index checker.
+    """
+    theProject = NWProject(dummyGUI)
+    theIndex = NWIndex(theProject, dummyGUI)
+
+    # Valid Index
+    theIndex._refIndex = {
+        "6a2d6d5f4f401": {
+            "T000000": {"tags": [], "updated": 1611922868},
+            "T000001": {"tags": [
+                [3, "@pov", "Jane"], [4, "@location", "Earth"]
+            ], "updated": 1611922868}
+        }
+    }
+    assert theIndex._checkRefIndex() is None
+
+    # Invalid Handle
+    theIndex._refIndex = {
+        "Ha2d6d5f4f401": {
+            "T000000": {"tags": [], "updated": 1611922868},
+            "T000001": {"tags": [
+                [3, "@pov", "Jane"], [4, "@location", "Earth"]
+            ], "updated": 1611922868}
+        }
+    }
+    with pytest.raises(KeyError):
+        theIndex._checkRefIndex()
+
+    # Invalid Title
+    theIndex._refIndex = {
+        "6a2d6d5f4f401": {
+            "T000000": {"tags": [], "updated": 1611922868},
+            "INVALID": {"tags": [
+                [3, "@pov", "Jane"], [4, "@location", "Earth"]
+            ], "updated": 1611922868}
+        }
+    }
+    with pytest.raises(KeyError):
+        theIndex._checkRefIndex()
+
+    # Missing 'tags'
+    theIndex._refIndex = {
+        "6a2d6d5f4f401": {
+            "T000000": {"tags": [], "updated": 1611922868},
+            "T000001": {"updated": 1611922868}
+        }
+    }
+    with pytest.raises(KeyError):
+        theIndex._checkRefIndex()
+
+    # Wrong Length of 'tags'
+    theIndex._refIndex = {
+        "6a2d6d5f4f401": {
+            "T000000": {"tags": [], "updated": 1611922868},
+            "T000001": {"tags": [
+                [3, "@pov", "Jane"], [4, "@location", "Earth", "Stuff"]
+            ], "updated": 1611922868}
+        }
+    }
+    with pytest.raises(IndexError):
+        theIndex._checkRefIndex()
+
+    # Wrong Type of 'tags' Entry 0
+    theIndex._refIndex = {
+        "6a2d6d5f4f401": {
+            "T000000": {"tags": [], "updated": 1611922868},
+            "T000001": {"tags": [
+                [3, "@pov", "Jane"], ["4", "@location", "Earth"]
+            ], "updated": 1611922868}
+        }
+    }
+    with pytest.raises(ValueError):
+        theIndex._checkRefIndex()
+
+    # Wrong Type of 'tags' Entry 1
+    theIndex._refIndex = {
+        "6a2d6d5f4f401": {
+            "T000000": {"tags": [], "updated": 1611922868},
+            "T000001": {"tags": [
+                [3, "@pov", "Jane"], [4, "@stuff", "Earth"]
+            ], "updated": 1611922868}
+        }
+    }
+    with pytest.raises(ValueError):
+        theIndex._checkRefIndex()
+
+    # Wrong Type of 'tags' Entry 1
+    theIndex._refIndex = {
+        "6a2d6d5f4f401": {
+            "T000000": {"tags": [], "updated": 1611922868},
+            "T000001": {"tags": [
+                [3, "@pov", "Jane"], [4, "@location", 123456]
+            ], "updated": 1611922868}
+        }
+    }
+    with pytest.raises(ValueError):
+        theIndex._checkRefIndex()
+
+    # Missing 'updated'
+    theIndex._refIndex = {
+        "6a2d6d5f4f401": {
+            "T000000": {"tags": [], "updated": 1611922868},
+            "T000001": {"tags": []}
+        }
+    }
+    with pytest.raises(KeyError):
+        theIndex._checkRefIndex()
+
+    # Wrong Type of 'updated' Entry 1
+    theIndex._refIndex = {
+        "6a2d6d5f4f401": {
+            "T000000": {"tags": [], "updated": 1611922868},
+            "T000001": {"tags": [], "updated": "1611922868"}
+        }
+    }
+    with pytest.raises(ValueError):
+        theIndex._checkRefIndex()
+
+# END Test testCoreIndex_CheckRefIndex
+
+@pytest.mark.core
+def testCoreIndex_CheckNovelNoteIndex(dummyGUI):
+    """Test the novel and note index checkers.
+    """
+    theProject = NWProject(dummyGUI)
+    theIndex = NWIndex(theProject, dummyGUI)
+
+    # Valid Index
+    theIndex._novelIndex = {
+        "53b69b83cdafc": {
+            "T000001": {
+                "level": "H1", "title": "My Novel", "layout": "TITLE", "synopsis": "text",
+                "cCount": 72, "wCount": 15, "pCount": 2, "updated": 1611922868
+            }
+        }
+    }
+    theIndex._noteIndex = theIndex._novelIndex.copy()
+    assert theIndex._checkNovelNoteIndex("novelIndex") is None
+    assert theIndex._checkNovelNoteIndex("noteIndex") is None
+    with pytest.raises(IndexError):
+        theIndex._checkNovelNoteIndex("notAnIndex")
+
+    # Invalid Handle
+    theIndex._novelIndex = {
+        "H3b69b83cdafc": {
+            "T000001": {
+                "level": "H1", "title": "My Novel", "layout": "TITLE", "synopsis": "text",
+                "cCount": 72, "wCount": 15, "pCount": 2, "updated": 1611922868
+            }
+        }
+    }
+    with pytest.raises(KeyError):
+        theIndex._checkNovelNoteIndex("novelIndex")
+
+    # Invalid Title
+    theIndex._novelIndex = {
+        "53b69b83cdafc": {
+            "INVALID": {
+                "level": "H1", "title": "My Novel", "layout": "TITLE", "synopsis": "text",
+                "cCount": 72, "wCount": 15, "pCount": 2, "updated": 1611922868
+            }
+        }
+    }
+    with pytest.raises(KeyError):
+        theIndex._checkNovelNoteIndex("novelIndex")
+
+    # Wrong Length
+    theIndex._novelIndex = {
+        "53b69b83cdafc": {
+            "T000001": {
+                "level": "H1", "title": "My Novel", "layout": "TITLE", "synopsis": "text",
+                "cCount": 72, "wCount": 15, "pCount": 2, "updated": 1611922868, "stuff": None
+            }
+        }
+    }
+    with pytest.raises(IndexError):
+        theIndex._checkNovelNoteIndex("novelIndex")
+
+    # Missing Keys
+    # ============
+
+    # Missing 'level'
+    theIndex._novelIndex = {
+        "53b69b83cdafc": {
+            "T000001": {
+                "stuff": "H1", "title": "My Novel", "layout": "TITLE", "synopsis": "text",
+                "cCount": 72, "wCount": 15, "pCount": 2, "updated": 1611922868
+            }
+        }
+    }
+    with pytest.raises(KeyError):
+        theIndex._checkNovelNoteIndex("novelIndex")
+
+    # Missing 'title'
+    theIndex._novelIndex = {
+        "53b69b83cdafc": {
+            "T000001": {
+                "level": "H1", "stuff": "My Novel", "layout": "TITLE", "synopsis": "text",
+                "cCount": 72, "wCount": 15, "pCount": 2, "updated": 1611922868
+            }
+        }
+    }
+    with pytest.raises(KeyError):
+        theIndex._checkNovelNoteIndex("novelIndex")
+
+    # Missing 'layout'
+    theIndex._novelIndex = {
+        "53b69b83cdafc": {
+            "T000001": {
+                "level": "H1", "title": "My Novel", "stuff": "TITLE", "synopsis": "text",
+                "cCount": 72, "wCount": 15, "pCount": 2, "updated": 1611922868
+            }
+        }
+    }
+    with pytest.raises(KeyError):
+        theIndex._checkNovelNoteIndex("novelIndex")
+
+    # Missing 'synopsis'
+    theIndex._novelIndex = {
+        "53b69b83cdafc": {
+            "T000001": {
+                "level": "H1", "title": "My Novel", "layout": "TITLE", "stuff": "text",
+                "cCount": 72, "wCount": 15, "pCount": 2, "updated": 1611922868
+            }
+        }
+    }
+    with pytest.raises(KeyError):
+        theIndex._checkNovelNoteIndex("novelIndex")
+
+    # Missing 'cCount'
+    theIndex._novelIndex = {
+        "53b69b83cdafc": {
+            "T000001": {
+                "level": "H1", "title": "My Novel", "layout": "TITLE", "synopsis": "text",
+                "stuff": 72, "wCount": 15, "pCount": 2, "updated": 1611922868
+            }
+        }
+    }
+    with pytest.raises(KeyError):
+        theIndex._checkNovelNoteIndex("novelIndex")
+
+    # Missing 'wCount'
+    theIndex._novelIndex = {
+        "53b69b83cdafc": {
+            "T000001": {
+                "level": "H1", "title": "My Novel", "layout": "TITLE", "synopsis": "text",
+                "cCount": 72, "stuff": 15, "pCount": 2, "updated": 1611922868
+            }
+        }
+    }
+    with pytest.raises(KeyError):
+        theIndex._checkNovelNoteIndex("novelIndex")
+
+    # Missing 'pCount'
+    theIndex._novelIndex = {
+        "53b69b83cdafc": {
+            "T000001": {
+                "level": "H1", "title": "My Novel", "layout": "TITLE", "synopsis": "text",
+                "cCount": 72, "wCount": 15, "stuff": 2, "updated": 1611922868
+            }
+        }
+    }
+    with pytest.raises(KeyError):
+        theIndex._checkNovelNoteIndex("novelIndex")
+
+    # Missing 'updated'
+    theIndex._novelIndex = {
+        "53b69b83cdafc": {
+            "T000001": {
+                "level": "H1", "title": "My Novel", "layout": "TITLE", "synopsis": "text",
+                "cCount": 72, "wCount": 15, "pCount": 2, "stuff": 1611922868
+            }
+        }
+    }
+    with pytest.raises(KeyError):
+        theIndex._checkNovelNoteIndex("novelIndex")
+
+    # Wrong Types
+    # ===========
+
+    # Wrong Type for 'level'
+    theIndex._novelIndex = {
+        "53b69b83cdafc": {
+            "T000001": {
+                "level": "XX", "title": "My Novel", "layout": "TITLE", "synopsis": "text",
+                "cCount": 72, "wCount": 15, "pCount": 2, "updated": 1611922868
+            }
+        }
+    }
+    with pytest.raises(ValueError):
+        theIndex._checkNovelNoteIndex("novelIndex")
+
+    # Wrong Type for 'title'
+    theIndex._novelIndex = {
+        "53b69b83cdafc": {
+            "T000001": {
+                "level": "H1", "title": 12345678, "layout": "TITLE", "synopsis": "text",
+                "cCount": 72, "wCount": 15, "pCount": 2, "updated": 1611922868
+            }
+        }
+    }
+    with pytest.raises(ValueError):
+        theIndex._checkNovelNoteIndex("novelIndex")
+
+    # Wrong Type for 'layout'
+    theIndex._novelIndex = {
+        "53b69b83cdafc": {
+            "T000001": {
+                "level": "H1", "title": "My Novel", "layout": "INVALID", "synopsis": "text",
+                "cCount": 72, "wCount": 15, "pCount": 2, "updated": 1611922868
+            }
+        }
+    }
+    with pytest.raises(ValueError):
+        theIndex._checkNovelNoteIndex("novelIndex")
+
+    # Wrong Type for 'synopsis'
+    theIndex._novelIndex = {
+        "53b69b83cdafc": {
+            "T000001": {
+                "level": "H1", "title": "My Novel", "layout": "TITLE", "synopsis": 123456,
+                "cCount": 72, "wCount": 15, "pCount": 2, "updated": 1611922868
+            }
+        }
+    }
+    with pytest.raises(ValueError):
+        theIndex._checkNovelNoteIndex("novelIndex")
+
+    # Wrong Type for 'cCount'
+    theIndex._novelIndex = {
+        "53b69b83cdafc": {
+            "T000001": {
+                "level": "H1", "title": "My Novel", "layout": "TITLE", "synopsis": "text",
+                "cCount": "72", "wCount": 15, "pCount": 2, "updated": 1611922868
+            }
+        }
+    }
+    with pytest.raises(ValueError):
+        theIndex._checkNovelNoteIndex("novelIndex")
+
+    # Wrong Type for 'wCount'
+    theIndex._novelIndex = {
+        "53b69b83cdafc": {
+            "T000001": {
+                "level": "H1", "title": "My Novel", "layout": "TITLE", "synopsis": "text",
+                "cCount": 72, "wCount": "15", "pCount": 2, "updated": 1611922868
+            }
+        }
+    }
+    with pytest.raises(ValueError):
+        theIndex._checkNovelNoteIndex("novelIndex")
+
+    # Wrong Type for 'pCount'
+    theIndex._novelIndex = {
+        "53b69b83cdafc": {
+            "T000001": {
+                "level": "H1", "title": "My Novel", "layout": "TITLE", "synopsis": "text",
+                "cCount": 72, "wCount": 15, "pCount": "2", "updated": 1611922868
+            }
+        }
+    }
+    with pytest.raises(ValueError):
+        theIndex._checkNovelNoteIndex("novelIndex")
+
+    # Wrong Type for 'updated'
+    theIndex._novelIndex = {
+        "53b69b83cdafc": {
+            "T000001": {
+                "level": "H1", "title": "My Novel", "layout": "TITLE", "synopsis": "text",
+                "cCount": 72, "wCount": 15, "pCount": 2, "updated": "1611922868"
+            }
+        }
+    }
+    with pytest.raises(ValueError):
+        theIndex._checkNovelNoteIndex("novelIndex")
+
+# END Test testCoreIndex_CheckNovelNoteIndex
+
+@pytest.mark.core
+def testCoreIndex_CheckTextCounts(dummyGUI):
+    """Test the text counts checker.
+    """
+    theProject = NWProject(dummyGUI)
+    theIndex = NWIndex(theProject, dummyGUI)
+
+    # Valid Index
+    theIndex._textCounts = {
+        "53b69b83cdafc": [72, 15, 2],
+        "974e400180a99": [210, 40, 2],
+    }
+    assert theIndex._checkTextCounts() is None
+
+    # Invalid Handle
+    theIndex._textCounts = {
+        "53b69b83cdafc": [72, 15, 2],
+        "h74e400180a99": [210, 40, 2],
+    }
+    with pytest.raises(KeyError):
+        theIndex._checkTextCounts()
+
+    # Wrong Length
+    theIndex._textCounts = {
+        "53b69b83cdafc": [72, 15, 2],
+        "974e400180a99": [210, 40, 2, 8],
+    }
+    with pytest.raises(IndexError):
+        theIndex._checkTextCounts()
+
+    # Type of Entry 0
+    theIndex._textCounts = {
+        "53b69b83cdafc": [72, 15, 2],
+        "974e400180a99": ["210", 40, 2],
+    }
+    with pytest.raises(ValueError):
+        theIndex._checkTextCounts()
+
+    # Type of Entry 1
+    theIndex._textCounts = {
+        "53b69b83cdafc": [72, 15, 2],
+        "974e400180a99": [210, "40", 2],
+    }
+    with pytest.raises(ValueError):
+        theIndex._checkTextCounts()
+
+    # Type of Entry 2
+    theIndex._textCounts = {
+        "53b69b83cdafc": [72, 15, 2],
+        "974e400180a99": [210, 40, "2"],
+    }
+    with pytest.raises(ValueError):
+        theIndex._checkTextCounts()
+
+# END Test testCoreIndex_CheckTextCounts