Screensharing stops working after reboot on 10.8 Server

Linc, thanks for your answer. I've seen this Thread before but it doesn't help at all. I've checked all the things mentioned there and found no way to get this working. I don't think it's a authorization issue because it worked for years...

Thanks a lot!

Yes Linc, we use Filemaker Server and a customized application on top. We have to update this application to get it running on newer FM versions as FM 11 will not run on 10.11. But we are on the way to get there. At the end of the day it's a management decision and you are completely right in asking this question.

Turned off Remote Management and switched over to Screen Sharing. It takes about 5 minutes before the server asks for username and password. 2 minutes later the authentication succeeds. Then "connecting" is displayed forever at the client. The server logs "unabel to get width and height" after 2 more minutes.

There's a display connected and detected by the system.

Actually there are two local admins, both are affected as well as network accounts.

We use the installed Screen Sharing App on the Clients, in this case 10.11 on my iMac.

Thanks again for your help Linc.

OK Linc, worth a try. I will have to find a suitable moment for doing a reboot next week and come back later. Thanks again and best regards.

Holy smoke this helped. Did a boot into single user and checked discs (just in case). Then boot into safe mode (shift at chime) where screensharing works. Now back in normal mode an screensharing is working again.

Thanks Linc, you are a godsend for Apple users. Ric