Hi Volunteers, I will be trying to be nice in putting this question, and doing my best to explain. I use thunderbird lightning calendar as my daily navigator. I connect by the 'CalDAV' protocol to my email/calendar provider. The connection link looks somewhat like this: https://.....com/interface/caldav.php/calendars/user@mail.com/calendar/ The idea was to sync my appointments to my mail host servers and have a safe backup like this. Now, the issue that comes in, is about time. For every new event I create the time changes unexpectedly on the day of the event by 2 hours difference. When I add a 'Reminder' it is even worse. It will change the time by 2 hours later instantly. I need to open the event again change it to 2 hours early (15.00 becomes 13.00) and then lightning will set the correct time (15.00) But....at the day the event takes place, again lightning will set the wrong time for the same event. Very unhandy. I started to check the system time of the o.s., which is correct now. I checked the bios time, which is correct. I checked 'timezone' under settings (calendar) . It says Europe which is correct. (By the way the provider servers are also in europe, it should be correct) Now, I cannot figure out what causes the issue. Maybe very far fetched, I hard copied the thunderbird profile I use from a windows thunderbird application to a linux thunderbird profile. Never had problems with that procedure. Could there be a reason for this lightning time issue hidden in there? Later I started using caldav to sync my messages to my provider servers' . I opened a ticket for my email provider explaining this problem, but they claim they have no answer for it. They state that for other mail applications like outlook calendar work good and the problem doesn't occur. Which is the point where I created this ticket and ask politely for your support. Thanks. Dirk.