Windows 7 VPN to SBS 2003 using PPTP

Question

This one has me really stumped. I have a client that want to VPN to her office from home PC, now the setup is bog standard.

OFFICE: SBS 2003 RRAS configured through wizard, have no probs connecting from any device anywhere ( almost )

HOME: linksys router, ( this one, brand new, also her third one ) PC DELL precision t3500.

Now, this has worked in the past, and tends to every now and then, but the VPN fails at username & password, end up with the usual 806 error and the server tells me that there was router / GRE issue. The wiered part is that this PC can connect to my server, other VPN servers I've set up, just about anywhere. Nope, its not the router as she also has two other laptops at home, they can connect just fine.

Have replaced routers, NIC'S and the PC ( for other reasons ) has had powersupply, motherboard, hardrive & nICS again, it's in a new state, just been re-installed from scratch. It just doesnt make sense.

Answer 1

Couple ideas:

Many 'home' routers (with 'VPN pass-thru') won't allow more than one outgoing VPN tunnel at a time (at least not to the same server).

If you connect to the VPN with one system, another on the (home) LAN won't work. If you disconnect from the VPN it will still often take a few minutes until the router clears it's tables; once that's done the VPN can then be connected to by different computer on the LAN (often rebooting the router will speed this up).

Another thing to check is hard-setting the VPN type to PPTP. I found this to be more of an issue with XP than Vista/7 but it's something (else) to try if you haven't.

Hope that helps...