When connecting to my company's Windows 2000 domain controller using Windows 7's built-in VPN connection, I can connect to network shares that are on the DC, but I cannot connect to any other servers on the network unless I use the server's IP address. The DC is also the receiving VPN server, so it is fairly obvious why I can connect to its shares, however I cannot determine the reason why I cannot connect to any other server using \\servername pathing. This includes using existing network drives that have no problem connecting when in the office, but give the Network Error message "Windows cannot access \\servername", as well as not being able to set up an Outlook 2007 profile with manual settings that point to our Exchange 2000 server. When trying to open the mapped drives that do not work I immediately get the Restoring Network Connections error message "An error occurred while reconnecting to X: to \\servername\share. Microsoft Windows Network: The network path was not found. This connection has not been restored." The account used to make the VPN connection is the same account used on XP SP3 computers that can access all servers and mapped shares. This account was used on one laptop to fully access all servers as recently as two weeks ago, but is now having the problem described above on two separate laptops with Windows 7 installed. All network drives are mapped with the specific user's credentials when directly connected to the office network and full connectivity has been verified from both laptops when physically connected to the network. When connecting to the servers via their IP addresses, I can access shared folders, but cannot access the mapped drives that point to the exact same folders from another Explorer window, even if both are open at the same time. I have tried adjusting the "Network security: LAN Manager authentication level" setting in Group Policy to "Send LM & NTLM responses" then "Send LM & NTLM - use NTLMv2 session security if negotiated" as suggested in another thread, but it with no change. We recently moved our DHCP service from our Exchange server to our DC server and have had odd issues with running network programs that seems to indicate a problem with our DNS service as well, but we have been able to circumvent the issue by turning off the "Automatically detect intranet network" setting in IE7 and IE8 via the Tools, Internet Options, Security, Local intranet, Sites dialog. Could the issue be related to the fact that we no longer have WINS services running in our DHCP service on the DC server that were running on the Exchange server? Any other suggestions about the issue? Update: I've found that when the VPN connection is made on the Win7 laptops, both show gateway addresses of 0.0.0.0 from the "ipconfig /all" command. I will do further research to try to determine if there is a specific setting that causes this to happen or if a recent update is causing the problem and update this topic again.

It's amazing how often a simple reboot can fix the most complex-appearing problems. My company is a CPA firm, which naturally means that we are in the thick of our busy time of the year. This is why I hadn't yet rebooted our DC/DHCP/DNS server, but it's also why the server locked up this morning (not to mention the fact that several of our most-used software packages are run on this server as well). When the lockup happened, it locked everyone's computers up, so we rebooted the server. After everyone was back up and running normally (and the panic had finally settled down), I began working on this issue again, hence the Update above. I decided to see if there were some Windows Firewall settings that were preventing the issue, so I started the VPN connection (using a 3G broadband router) and found that the mapped drives are available again. The issue with the "Open File - Security Warning" appearing when running network programs with the "Automatically detect intranet network" setting enabled is still unresolved, but it is a much smaller issue than the VPN problem.