Take a look at CloseFiles.pl even though you can't run it. What function does it call in Win32-Lanman? That might be suggestive.

I think it might be wiser to force the handle closed than to just remove the locks. I know Process Explorer (from Sysinternals) does it. Mark might explain how in one of the articles. It probably involves native NT calls, bypassing the Win32 API layer.

—John