diff --git a/templates/exam-show.hamlet b/templates/exam-show.hamlet
index 2224c91ed..c3b7c2a57 100644
--- a/templates/exam-show.hamlet
+++ b/templates/exam-show.hamlet
@@ -237,8 +237,8 @@ $if not (null occurrences)
                 $maybe (Entity _ User{userScheduleOccurrenceDisplayDefault}) <- mAuth
                   <td .table__td>
                     <div .table__td-content>
-                      <a .btn .btn-primary href=@{CExamR tid ssh csh examn (EScheduleOptSetR examOccurrenceName (not (maybe userScheduleOccurrenceDisplayDefault examOccurrenceScheduleOptOpt mEOScheduleOpt)))}>
-                        _{bool MsgScheduleOptIn MsgScheduleOptOut (maybe userScheduleOccurrenceDisplayDefault examOccurrenceScheduleOptOpt mEOScheduleOpt)}
+                      <a .btn .btn-primary href=@{CExamR tid ssh csh examn (EScheduleOptSetR examOccurrenceName (not (maybe (registered && userScheduleOccurrenceDisplayDefault) examOccurrenceScheduleOptOpt mEOScheduleOpt)))}>
+                        _{bool MsgScheduleOptIn MsgScheduleOptOut (maybe (registered && userScheduleOccurrenceDisplayDefault) examOccurrenceScheduleOptOpt mEOScheduleOpt)}
                       $if is _Just mEOScheduleOpt
                         <a .btn .btn-primary href=@{CExamR tid ssh csh examn (EScheduleOptDelR examOccurrenceName)}>
                           _{MsgScheduleOptDelete}