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vpn client error 51 windows xp

Installed vpn client on windows xp sp2. Restarted and launched the client. Received the following error message.

"Error 51: UNable to communicate with the VPN subsystem.

Please make sure that you have at least one network interface that is current active and has an IP address and start this application again."

Tried to uninstall and received blue screen of death.

Anybody familiar with this problem?


Re: vpn client error 51 windows xp

Hi Adam, have not faced this issue yet but have read some arcticles on this error 51 pointing to mostly MAC OS's and not neccesarily on XP, seems installation of vpn client somehow turns on Internet sharing on the system causing this error.. but looking into XP internet sharing you would need at least two NICS to turn on XP internet sharing.. perhaps see if this could be issue on the machine.

Also see some interesting threads at netpro

the bug ID is not much of a help but if you read the original poster reporting of a another adapter being created on XP this tends me to believe the theory of internet sharing turned on.. well.. at least is worth the try looking into this intenet sharring..




Re: vpn client error 51 windows xp

Thanks Jorge. Yes I did see all the posts dealing with MAC OS X when googling the error message. Internet connection sharing is not enabled.

Seems strange I get a blue screen when I attempt to uninstall. Makes me think there's more wrong than just the client install.

New Member

vpn client error 51 windows xp

I got this error 51 on my windows XP, and thing that worked for me was to stop and start "Cisco Systems, Inc. VPN Service" in Control Panel --> Administrative Tools --> Services. This is somewhat related to the solution described here: