In a small shop with an NT4 PDC, I've been trying to connect some new machines. The clients are Windows 7 professional, 64-bit. Trying to map a network drive from the PDC fails (invalid username/password), so does trying to join the domain. I've tried user-pass, user/domain-pass, etc., no luck. Finally, I went over to the NT4 server, and took a look in the event log. No reports of any failed logins at all. Now I'm confused. I made sure that the Win7 clients have the client for Microsoft networks, and that they have file sharing enabled. Just for fun, I even tried with their firewalls turned off. No luck. Is there something I'm missing here?