Since I accidently changed my system clock to a time in the future and set it back correctly, I get an error when Maple starts.
It's an license-error more specific: FlexIm error: -88,309 "System clock has been set back"
Maple asks to reactivate, once done that successfully Maple says that after starting Maple again everything will work properly. But it doesn't work, I get once again the same error and the question to reactivate.
The error is known by MapleSoft, I got this information:
"FLEXlm checks the computer for files with a timestamp beyond the current date. If there are files with a creation date in the future of what the current system clock reads, FLEXlm will return this error. These files must have been created when the clock was set incorrectly. We suggest the user conducts an advanced file search to find the files that are causing the problem."