Did you make sure that the folders for Ad-aware/Lavasoft was deleted in C:\Program Files\? Also, does the update work after you install it?
Uninstall it...delete the folders if they still exist. Restart and reinstall. Check for updates. Try running it again. If error occurs again, give me the exact message (both English and German).
Uninstall it...delete the folders if they still exist. Restart and reinstall. Check for updates. Try running it again. If error occurs again, give me the exact message (both English and German).