Thanks four your reaction. However, I'm sad to say that this didn't work either. I dowloaded both Java and Limewire, deleted previous versions of the spftware through the ad/remove software screen, and searched the drive for any remaining Limewire files, which I deleted as well.

When starting Limewire, I was taken through the setup-part (what is your connection, where do you want the files to be saved etc.). Then I even restarted the computer. But after starting Limewire, the same problem persists.

I hope you have any other suggestions!