1. The user's account doesn't have permission to read that directory.

2. The XP Tablet edition you have can't join a domain.

I can't answer either issue since I'm not there to check permissions and versions of this OS. You may have to ask Microsoft about the capabilities of the Tablet OS when connecting to a domain.

The last item is the firewall. I can't count how many times it gets in the way and needs configuring. But any IT worth their salt would configure that proper.