Adobe Acrobat won't open on my mac

Since a long time my Adobe Acrobat won't open. I tried to deinstal and reinstal several times but nothing seems to change. When I try to open the program, the icon appears for a second in the dock but then dissappears again and the Acrobat Licensing Application opens saying:

"Leider ist ein Fehler aufgetreten" (Unfortunately an error appeared) and "Starten Sie zuerst Acrobat oder wenden Sie sich an Ihren Administrator." (Start Acrobat first or contact you admin)

I've tried a lot of things but can't make it work which is very annoying. All the other Adobe programs work as usual.
I'd be very glad about help!