Cisco Error 51: Unable to communicate to the VPN subsystem
Posted on July 28th, 2008 by JeffIf you’re running Cisco’s VPNClient on a Macintosh, you might run into Error 51 from time to time. Thanks to a blog posting on Anders.com for the solution. In Terminal, run the following command:
sudo /System/Library/StartupItems/CiscoVPN/CiscoVPN restart



