diff --git a/SoObjects/Appointments/SOGoAppointmentFolder.m b/SoObjects/Appointments/SOGoAppointmentFolder.m
index 0c02f06c7..9749dbcb6 100644
--- a/SoObjects/Appointments/SOGoAppointmentFolder.m
+++ b/SoObjects/Appointments/SOGoAppointmentFolder.m
@@ -3367,7 +3367,7 @@ firstInstanceCalendarDateRange: (NGCalendarDateRange *) fir
   // we generate a new UID based on a GUID
   uid = [event uid];
 
-  if (![uid length] ||
+  if (![uid length] || [uid length] > 250 ||
       [uid rangeOfCharacterFromSet: [NSCharacterSet characterSetWithCharactersInString: @"+/"]].location != NSNotFound)
     {
       uid = [self globallyUniqueObjectId];
diff --git a/SoObjects/Appointments/iCalEvent+SOGo.m b/SoObjects/Appointments/iCalEvent+SOGo.m
index 1710a91c7..0e710affa 100644
--- a/SoObjects/Appointments/iCalEvent+SOGo.m
+++ b/SoObjects/Appointments/iCalEvent+SOGo.m
@@ -90,6 +90,9 @@
   startDate = [self startDate];
   endDate = [self endDate];
   uid = [self uid];
+  if ([uid length] > 255)
+    uid = [uid substringToIndex: 255];
+
   title = [self summary];
   if (![title isNotNull])
     title = @"";