Thanks to all for your replies, I had the same issue and was able to solve it: I also received the FileMinimizer Suite because I purchased an upgrade to Nero 9 and initially thought it could be useful... However, I could not find the extension using ShellExView. But after having a closer look to the folder that contains FileMinimizer, I noticed the following two files:
and decided to rename their extension to .NOTEXE.
After re-starting the system, the problem was solved and FileMinimizer still seems to work. I'll probably de-install it anyway however, because I don't like that kind of "marketing" at all...