I'm writing a small tool for ArcMap that invokes one of the tools built into it. For some reason though the tool, and Arc in general, is kind of picky when dealing with network drives. Say I have a network share mapped as the P: drive. The share itself is \\Canberra\Projects. Now, when I send a parameter into the tool that lists the path of a file, I need to send it in as \\Canberra\Projects\file.txt rather than P:\file.txt.

I can't be sure in advance what the drive mappings might be for a user, so how do I work out if a drive is a network connection rather than a physical drive and how do I extract the network mapping for that drive?