Yes, but when you open, and check the return value as recommended previously with the "or die $!" conditional, what error gets printed? That's an important part of the puzzle, you've got to check it.

There is a possibility that you don't have write permissions in the network drive, or that your script isn't running with the correct permissions (especially if it's a CGI script, or being called by a CGI script, for example).

Or there could be a network issue. Just try it with that "open FH, '>', $filename or die $!" statement and see that the error message is.