Problem with the Layer-Manager

Hello!

I'm using DS since a quiet long time and have recently purchased and installed the Professional version. Since a crash of the program (still with normal version) the following error message appears by clicking the Layer Manager::

: '_LAYER

"Error"

So I cannot open the Layer Manager anymore. Even after a deinstallation and subsequent reinstallation (now with professional version) the error could not be solved? Can someone help me?