diff --git a/CHANGELOG.md b/CHANGELOG.md
index 85d7e81d8..e295aa8a4 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,8 @@ All notable changes to this project will be documented in this file.
 ### Removed
 ### Fixed
 
+- [janitor] `update-idents` unables to process when some Error docs are in the index.
+
 ## [1.11.0] - 2024-01-12
 
 ### Added
diff --git a/src/Monocle/Backend/Documents.hs b/src/Monocle/Backend/Documents.hs
index 393f7022c..3c557b7dc 100644
--- a/src/Monocle/Backend/Documents.hs
+++ b/src/Monocle/Backend/Documents.hs
@@ -319,6 +319,7 @@ instance FromJSON EChangeState where
       )
 
 -- | When adding new document type, update the `instance FromJSON EDocType` too.
+-- | and please make sure to update `allEventTypes` accordingly
 data EDocType
   = EChangeCreatedEvent
   | EChangeMergedEvent
@@ -339,7 +340,7 @@ data EDocType
 
 allEventTypes :: [EDocType]
 allEventTypes =
-  filter (`notElem` [EChangeDoc, EOrphanTaskData, ECachedAuthor]) [minBound .. maxBound]
+  filter (`notElem` [EChangeDoc, EOrphanTaskData, ECachedAuthor, EErrorDoc]) [minBound .. maxBound]
 
 instance From EDocType Text where
   from = \case