Windows adds a '(1)' before the extension copying files from the temporary internet folder. Maybe XP's system restore (or something) does the same thing?
If you can't (or don't want to) reload to get a good dragon helm, you could always use
DAD's item editor to recreate the lost one. There is also a
mirror site {DDIE.exe is the executable (112KB), DDIE_ZIPPED.exe is the installer (2.4MB)}.
