Cisco VPNClient - Launch issues in Mac OS X 10.5 & 10.6

Ben Greiner -


If your Cisco VPNClient application will not launch. Maybe it's throwing up "Error 51: Unable to communicate with the VPN subsystem." and you don't want to take the time to restart your Mac to fix the issue (or maybe a restart doesn't fix the issue!) then try this...

  1. Open Terminal and type: sudo kextunload /System/Library/Extensions/CiscoVPN.kext
  2. After authenticating type: sudo kextload /System/Library/Extensions/CiscoVPN.kext
  3. Quit Terminal and launch Cisco VPNClient!
Another option is to ditch the Cisco VPNClient and replace it with Shimo.
Contact us if you have any questions or continue to experience problems with your technology.
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