Windows XP, VPNs and DNS

I have a work-supplied laptop.  Until this week, whenever I activated the PPTP VPN to work, I was able to resolve all of our internal servers by DNS name.  This is good, it means I can navigate our network at work without remembering IP addresses.

This week Iโ€™m on call.  I had to VPN in to check out a failed Internet connection, and found to my horror that DNS resolution no longer worked.  I pondered for a moment, and then hard-coded the DNS server for the underlying network device to the work DNS servers and was able to get on with the job.

Iโ€™ve just been looking for what the heck has gone wrong; my home PC is able to open up the same VPN connection (I checked every single setting) and DNS resolution works.  What I found was a page describing a registry edit that fixes the problem.  Did said regedit, and presto, the VPN from the laptop works again.  The thing that bugs me is I donโ€™t know how that setting got changed.  Mindboggling.

For the record, in case that page goes away, edit HKLM\SYSTEM\CurrentControlSet\Services\Tcpip\Linkage, double-click Bind and move the NdisWanIp entry to the top of the list.

Windows.  Feh.