It's counterintuitive, but first install Nero 5 and then try the uninstall. Something has gone wonky in the uninstall routine and that is usually fixed by re-installing the software. If it will re-install OK you should be able to go ahead and successfully uninstall. If the program has its own uninstaller, use that. Also more programs now offer an uninstall utility on their web sites. This mostly applies to printers, video drivers and such but see if Nero has such a utility.