Browsing the network via a Cisco VPN

Hello.

Windows SBS 2003 domain. One server, which is the SBS 2003 server.

I have Windows XP Pro SP2 laptops that connect to the network via a Cisco
Vpn to a PIX firewall. The PIX uses a Windows user group to allow access to
the VPN. After connecting, they browse the shared folders on the SBS server.

I have one laptop, however, that only sees a few folders, similiar to when a
locally connected PC loses connectivity to the network. It shows only what it
remembers of the network. All shares cannot be accessed.

I can take another laptop, connect via the VPN logging on as the user of the
first laptop. Once I log in this way, not only can I browse all network
shares, I can also now browse all network shares from the first laptop, which
is logged on as the same user.

It seems that the first laptop is not doing something with the credentials,
and after I log on from the second laptop and authenticate, then that user is
recognized and that user has access to everything from either laptop.

The first laptop does cache logon credentials in group policy under
Interactive Logon - the default of 10.

Only one laptop gives me this problem.

The Cisco VPN client authenticates with a windows user group to allow
access. All members of this user group are able to connect via the Cisco VPN.
The logon I am using is a member of this group. (From a different computer
that user can browse the network fine.)

I am out of ideas as to what to look for. Why does the first laptop not
authenticate the user with the domain? It does not even bring up a logon
dialogue box to connect to a share, as happens when accessing those shares
from a computer and user account that are not part of the domain.

Thank you in advance for any help you can give.

KT