This should not happen. You should be able, running as Administrator, to Register and UNregister dll's allright. HOW EXACTLY did you run the command? WHICH EXACT error did you get? Sorry, I have a Hungarian OS, I try to translate what I get: "shimgvw.dll module has been successfully loadad but the following entry point not found: DllUnregisterServer Make sure that that 'shimgvw.dll ' os a valid DLL or OCX file and try again" Well, then I guess you will have to live with that "smart" feature enabled. Out of curiosity, WHAT are the contents of the keys: HKEY_CLASSES_ROOT\.jpeg HKEY_CLASSES_ROOT\.jpg HKEY_CLASSES_ROOT\.bmp on your system? jaclaz In my case they are also defaulted to "image" but I tried to delete them, but nothing happened.