diff --git a/src/Foundation.hs b/src/Foundation.hs
index 51062691d..519ba6ea9 100644
--- a/src/Foundation.hs
+++ b/src/Foundation.hs
@@ -309,11 +309,25 @@ knownTags = Map.fromList -- should not throw exceptions, i.e. no getBy404 or req
         Entity cid _ <- MaybeT . getBy $ CourseTermShort tid csh
         Entity _sid Sheet{..} <- MaybeT . getBy $ CourseSheet cid shn
         cTime <- liftIO getCurrentTime
+        let
+          visible = NTop sheetVisibleFrom <= NTop (Just cTime)
+          active = sheetActiveFrom <= cTime && cTime <= sheetActiveTo
+
+        guard visible
+
+        case subRoute of
+          SFileR SheetExercise _ -> guard $ sheetActiveFrom <= cTime
+          SFileR SheetHint     _ -> guard $ maybe False (<= cTime) sheetHintFrom
+          SFileR SheetSolution _ -> guard $ maybe False (<= cTime) sheetSolutionFrom
+          SubmissionNewR         -> guard   active
+          SubmissionR _ _        -> guard   active
+          _                      -> return ()
+
+        return Authorized
+        
         let started = sheetActiveFrom <= cTime  ||  NTop sheetVisibleFrom <= (NTop $ Just cTime)
         case subRoute of
           SFileR SheetExercise _ -> guard started
-          SFileR SheetHint     _ -> guard $ maybe False (<= cTime) sheetHintFrom
-          SFileR SheetSolution _ -> guard $ maybe False (<= cTime) sheetSolutionFrom
           SFileR SheetMarking  _ -> mzero -- only for correctors and lecturers
           SubmissionNewR         -> guard $ sheetActiveFrom <= cTime && cTime <= sheetActiveTo
           SubmissionR _ _        -> guard $ sheetActiveFrom <= cTime && cTime <= sheetActiveTo