Dear people,
The problem occured for the third time on my pc today, the first time it just dissappeard after shutting down anyway and starting up the next day. Second time it got away by checking the disk when rebooting with the command: chkdsk /f in cmd as admin. This time it went away after starting windows in safe mode, then shutting down and restarting with my ethernet cable unplugged... so I guess this ethernet cable had something to do with that plug&play problem...
Hopfully this is helpfull for some people out there,
Good luck
seppe