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 I’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.
I’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 don’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.