VPN connection problems in Windows Vista, error 609

I have a PPTP VPN connection set up on a Fortigate 60 firewall, and it had worked fine when everyone was using Windows XP. Then I got a laptop that had Windows Vista installed. Things were fine in the beginning, and then all of a sudden the VPN didn't work anymore. I would try to dial in, but it would fail right away saying a connection couldn't be established. I knew it was working though because other users were still using it, and I was able to connect with the Windows XP install I had running through Microsoft Virtual PC. I deleted and recreated the VPN connections with no luck. I checked the firewall configuration and couldn't find anything out of the ordinary. Searching the Internet didn't do much good for a while either. I finally found the answer tonight when I got an error 609 "A device type that was specified does not exist". It gave me something to search on, and sure enough it led me to something that fixed it right away. Apparently it can be caused by L2TP or PPTP not being installed, or else it's corrupt. There are foud small commands you can use from the command prompt to fix this. Open the command prompt, then enter and run these four commands in order:

netcfg -u MS_L2TP
netcfg -u MS_PPTP
netcfg -l %windir%\inf\netrast.inf -c p -i MS_PPTP
netcfg -l %windir%\inf\netrast.inf -c p -i MS_L2TP

This will reinstall PPTP and L2TP support on your Vista computer, which will then allow you to use those protocols. For more information, or to see the original source, check out Microsoft KB 953795.