diff --git a/src/Handler/Exam/AutoOccurrence.hs b/src/Handler/Exam/AutoOccurrence.hs
index 9b8bff23b..04460a2b0 100644
--- a/src/Handler/Exam/AutoOccurrence.hs
+++ b/src/Handler/Exam/AutoOccurrence.hs
@@ -165,7 +165,7 @@ postEAutoOccurrenceR tid ssh csh examn = do
               occMappingRule = examOccurrenceMappingRule eaofMapping
 
               loadProp curr max'
-                | Just max'' <- max', max'' /= 0
+                | Just max'' <- assertM (/= 0) max'
                 = MsgProportion (toMessage curr) (toMessage max'') (toRational curr / toRational max'')
                 | otherwise
                 = MsgProportionNoRatio (toMessage curr) $ maybe "∞" toMessage max'
diff --git a/templates/widgets/massinput/examRooms/layout.hamlet b/templates/widgets/massinput/examRooms/layout.hamlet
index 7d7c5b6d9..6f23215d7 100644
--- a/templates/widgets/massinput/examRooms/layout.hamlet
+++ b/templates/widgets/massinput/examRooms/layout.hamlet
@@ -18,7 +18,7 @@ $newline never
     <tr>
       <td>
       <td>
-      <td .explanation> _{MsgExamRoomCapacityTip}
+      <td .explanation>_{MsgExamRoomCapacityTip}
       <td>
       <td>
       <td>