Error 51: Unable to communicate with the VPN subsystem
I upgraded Mac OS X to 10.5.8. I did the upgrade after my hard drive died and imported my profile from an old backup. When I tried to run my Cisco VPN client that I use for work, I was given this error:
Error 51: Unable to communicate with the VPN subsystem
First, I read that I could do this in the terminal:
Since I don’t have a CiscoVPN directory under startup items, that didn’t help me. Then I read that you need to to repair disk permissions using disk utility. I did that and it found several inconsistencies. Good stuff, though, it also did not solve my problem.
Then, I read that I could do this:
The command didn’t produce any output, nor did it fix my problem.
Finally, I came across a site that told me to do this:
$ sudo kextload /System/Library/Extensions/CiscoVPN.kext
This finally fixed my problem. Here is the sequence of commands that I ran and the output:
kextunload: unload kext /System/Library/Extensions/CiscoVPN.kext failed
$ sudo kextload /System/Library/Extensions/CiscoVPN.kext
kextload: /System/Library/Extensions/CiscoVPN.kext loaded successfully
$ sudo kextunload /System/Library/Extensions/CiscoVPN.kext
kextunload: unload kext /System/Library/Extensions/CiscoVPN.kext succeeded
$ sudo kextload /System/Library/Extensions/CiscoVPN.kext
kextload: /System/Library/Extensions/CiscoVPN.kext loaded successfully
Hopefully, this will save someone some time.
Tags: CiscoVPN
October 19th, 2009 at 8:05 pm
Thank you so much for posting this, it worked like a charm!
October 19th, 2009 at 9:07 pm
Glad I could help.
January 22nd, 2010 at 10:51 am
Thanks, Kris. I tried a lot of other Terminal stuff, but only your fix worked for me.
David