If in desperation, you can export the drive where your file is, "net use" the share to some free drive letter (meaning, mount the share on a drive) and then try to have your way with the file.
This does often work on NT (but reportedly fails on Win2k) - and I have used it often times yo snidely replace locked copies of system dlls (kids, do not try this at home - i thrashed ad least one machine with this trick...)
Not the cleanest approach, but ehi.

Cheers, alf