[captainmuon]

You could make it so that an application holding a file handle will always see this filename existing as long as the file is open. This is similar too, but not quite, what happens under Linux (the filename goes away, but the open file is still accessible as long as one process holds an open handle).

Or, if you wanted to be extra careful, just introduce a new locking flag (LOCK_DONT_LOCK_CAN_DELETE or whatever :-)). Then bug the authors of the most popular editors and the most buggy applications (which block files unneccesarily) to set the flag. If you want to, you could create a compatibility shim to force enable / disable this feature for a given application. (Edit: apparently this flag already exists? FILE_SHARE_DELETE?)

This is tricky, but probably not harder than e.g. modernizing the console subsystem.