This morning I got this message when attempting to connect to my VPN on OSX Mountain Lion:
An error (status 244) ocurred while trying to check the security of the ... configuration.
Please quit and relaunch Tunnelblick. If the problem persists, please reinstall Tunnelblick.
It turned out that Verizon Wireless VZAccess tool I installed last night changed permissions of my /Applications folder so it is writable by any user. Tunnelblick makes sure that the folder(s) it is in do not have such lax permissions, so it would not connect until I did this:
sudo chmod o-w /Applications
Probably you would get the same result by running Repair Permissions, but I have never done that myself so I am not sure if that may negatively affect anything else on your system.