diff --git a/src/Handler/Submission.hs b/src/Handler/Submission.hs
index ca79f978d..085957464 100644
--- a/src/Handler/Submission.hs
+++ b/src/Handler/Submission.hs
@@ -314,47 +314,48 @@ submissionHelper tid ssh csh shn mcid = do
     csheet@(Entity shid Sheet{..})  <- fetchSheet tid ssh csh shn
     maySubmit  <- (== Authorized) <$> evalAccessDB actionUrl True
     isLecturer <- (== Authorized) <$> evalAccessDB (CSheetR tid ssh csh shn SSubsR) True
+
+    submissions <- E.select . E.from $ \(submission `E.InnerJoin` submissionUser) -> do
+      E.on (submission E.^. SubmissionId E.==. submissionUser E.^. SubmissionUserSubmission)
+      E.where_ $ submissionUser E.^. SubmissionUserUser   E.==. E.val uid
+           E.&&. submission     E.^. SubmissionSheet    E.==. E.val shid
+      return $ submission E.^. SubmissionId
+    case (msmid, submissions) of
+      (Nothing, E.Value smid : _) -> do
+        cID <- encrypt smid
+        addMessageI Info MsgSubmissionAlreadyExists
+        redirect $ CSubmissionR tid ssh csh shn cID SubShowR
+      _other -> return ()
+  
     case (msmid, sheetGrouping) of
       (Nothing, Arbitrary maxBuddies) -> do
-        submissions <- E.select . E.from $ \(submission `E.InnerJoin` submissionUser) -> do
-          E.on (submission E.^. SubmissionId E.==. submissionUser E.^. SubmissionUserSubmission)
-          E.where_ $ submissionUser E.^. SubmissionUserUser   E.==. E.val uid
-               E.&&. submission     E.^. SubmissionSheet    E.==. E.val shid
-          return $ submission E.^. SubmissionId
-        -- logDebugS "Submission.DUPLICATENEW" (tshow submissions)
-        case submissions of
-          []    -> do
-            -- fetch buddies from previous submission in this course
-            buddies <- E.select . E.from $ \(submissionUser `E.InnerJoin` user) -> do
-              E.on (submissionUser E.^. SubmissionUserUser E.==. user E.^. UserId)
-              let oldids = E.subList_select . E.from $ \(sheet `E.InnerJoin` submission `E.InnerJoin` subUser `E.InnerJoin` submissionEdit) -> do
-                    E.on (submissionEdit E.^. SubmissionEditSubmission E.==. submission E.^. SubmissionId)
-                    E.on (subUser        E.^. SubmissionUserSubmission E.==. submission E.^. SubmissionId)
-                    E.on (sheet E.^. SheetId E.==. submission E.^. SubmissionSheet)
-                    E.where_ $  subUser E.^. SubmissionUserUser E.==. E.val uid
-                          E.&&. sheet   E.^.        SheetCourse E.==. E.val sheetCourse
-                    E.orderBy [E.desc $ submissionEdit E.^. SubmissionEditTime]
-                    E.limit 1
-                    return $ submission E.^. SubmissionId
-              E.where_ $  submissionUser E.^. SubmissionUserSubmission `E.in_` oldids
-                    E.&&. submissionUser E.^. SubmissionUserUser E.!=. E.val uid
-              E.orderBy  [E.asc $ user E.^. UserEmail]
-              return $ user E.^. UserId
-            return ( csheet
-                   , buddies
-                     & map (Right . E.unValue)
-                     & Set.fromList
-                     & assertM' ((<= maxBuddies) . fromIntegral . Set.size . bool id (Set.insert $ Right uid) (not isLecturer))
-                     & fromMaybe Set.empty
-                   , []
-                   , maySubmit
-                   , isLecturer
-                   , not isLecturer
-                   )
-          (E.Value smid:_) -> do
-            cID <- encrypt smid
-            addMessageI Info MsgSubmissionAlreadyExists
-            redirect $ CSubmissionR tid ssh csh shn cID SubShowR
+        -- fetch buddies from previous submission in this course
+        buddies <- E.select . E.from $ \(submissionUser `E.InnerJoin` user) -> do
+          E.on (submissionUser E.^. SubmissionUserUser E.==. user E.^. UserId)
+          let oldids = E.subList_select . E.from $ \(sheet `E.InnerJoin` submission `E.InnerJoin` subUser `E.InnerJoin` submissionEdit) -> do
+                E.on (submissionEdit E.^. SubmissionEditSubmission E.==. submission E.^. SubmissionId)
+                E.on (subUser        E.^. SubmissionUserSubmission E.==. submission E.^. SubmissionId)
+                E.on (sheet E.^. SheetId E.==. submission E.^. SubmissionSheet)
+                E.where_ $  subUser E.^. SubmissionUserUser E.==. E.val uid
+                      E.&&. sheet   E.^.        SheetCourse E.==. E.val sheetCourse
+                E.orderBy [E.desc $ submissionEdit E.^. SubmissionEditTime]
+                E.limit 1
+                return $ submission E.^. SubmissionId
+          E.where_ $  submissionUser E.^. SubmissionUserSubmission `E.in_` oldids
+                E.&&. submissionUser E.^. SubmissionUserUser E.!=. E.val uid
+          E.orderBy  [E.asc $ user E.^. UserEmail]
+          return $ user E.^. UserId
+        return ( csheet
+               , buddies
+                 & map (Right . E.unValue)
+                 & Set.fromList
+                 & assertM' ((<= maxBuddies) . fromIntegral . Set.size . bool id (Set.insert $ Right uid) (not isLecturer))
+                 & fromMaybe Set.empty
+               , []
+               , maySubmit
+               , isLecturer
+               , not isLecturer
+               )
       (Nothing, _) -> return (csheet, Set.empty, [], maySubmit, isLecturer, not isLecturer) -- TODO: Return registered group members
       (Just smid, _) -> do
         void $ submissionMatchesSheet tid ssh csh shn (fromJust mcid)