diff --git a/src/Foundation.hs b/src/Foundation.hs
index 8d338c7f0..32af16476 100644
--- a/src/Foundation.hs
+++ b/src/Foundation.hs
@@ -473,12 +473,11 @@ tagAccessPredicate AuthTime = APDB $ \route _ -> case route of
     case mbc of
       (Just (Entity _ Course{courseRegisterFrom, courseRegisterTo}))
         | not registered
-        , Just regFrom <- courseRegisterFrom -- Nothing = no registration
-        , regFrom <= now
-        , maybe True (now <=) courseRegisterTo -> return Authorized
+        , maybe False (now >=) courseRegisterFrom -- Nothing => no registration allowed
+        , maybe True  (now <=) courseRegisterTo -> return Authorized
       (Just (Entity _ Course{courseDeregisterUntil}))
         | registered
-        , maybe True (now <=) courseDeregisterUntil -> return Authorized
+        , maybe True  (now <=) courseDeregisterUntil -> return Authorized
       _other -> unauthorizedI MsgUnauthorizedCourseTime
 
   MessageR cID -> maybeT (unauthorizedI MsgUnauthorizedSystemMessageTime) $ do