diff --git a/src/Foundation.hs b/src/Foundation.hs
index 8b2769cea..88b202949 100644
--- a/src/Foundation.hs
+++ b/src/Foundation.hs
@@ -652,6 +652,7 @@ tagAccessPredicate AuthTime = APDB $ \mAuthId route _ -> case route of
       SFileR SheetExercise _ -> guard $ sheetActiveFrom <= cTime
       SFileR SheetHint     _ -> guard $ maybe False (<= cTime) sheetHintFrom
       SFileR SheetSolution _ -> guard $ maybe False (<= cTime) sheetSolutionFrom
+      SFileR _             _ -> mzero
       SubmissionNewR         -> guard   active
       SubmissionR _ SAssignR -> guard   marking -- Correctors can only be assigned when the Sheet is inactive, since submissions are subject to change
       SubmissionR _ _        -> guard   active