Thursday, July 8, 2010

OpenVPN in Windows 7

I often need to work remotely from work, luckily my work has a VPN server that allows me to get access to the companies internal resources. I have been using OpenVPN in Windows XP for a long time to do this, through the use of OpenVPN GUI. Well when I got a new laptop it came with Windows 7 installed. So one of the first things I did was set up my development environment which required me to get into some of the file shares inside of my companies network. I thought it wouldn't be a problem at all to do, I installed OpenVPN GUI and just copied over my configuration and key files. When I went to connect I got quite an interesting error:

Thu Jul 08 23:05:33 2010 ROUTE: route addition failed using CreateIpForwardEntry: One or more arguments are not correct.   [if_index=16]

It turns out to be very simple to fix. In Windows 7 and I believe in Vista you need to do a few extra steps to get OpenVPN GUI to work with Windows 7. First you need to go C:\Program Files\OpenVPN\Bin and make sure openvpn-gui.exe is always started as Administrator (in the compatibility menu of the file properties). Then you will need to edit your configuration file and add two lines after the line that describes your cipher:

route-method exe

route-delay 2

That should do it. Let me know if you have any questions.