Maybe this will help. The part in bold might help.
I recently encountered an issue with Windows 7 Professional connecting to an older Snap Server. After some research, I found that this problem originated in Vista, and is resolved in Windows 7 by the same method.
To use a login script to map a network drive to an older Snap Server in Vista or 7 Professional, you first have to
create a local user account on the Snap Server, even if it is joined to the domain.
Then, you have to make the following changes on the Windows client.
. Go to Administrative Tools
. Double Click Local Security Policy
. On the left pane, click to expand Local Policies
. On the left pane, click on Security Options
. Now, on the right pane, near the bottom, click on Network Security LAN Manager Authentication Level
. On the drop down, change the default setting (NTLMv2 only) to Send LM & NTLM - use NTLMv2 session if negotiated
Then, just add the username and password into the network mapping command in the login script.
Example;
Net use X:
\snapservernameshare password /USER:snaperservernameusername
http://www.bostonhelpdesk.com/blog/?p=41