"The necessary VPN sub-system is not available. . ." Error
Hello, I am running WinXP and have recently upgraded to a new version of the Cisco Systems VPN Client (v3.5.1). When I try to run the new verison, it gives me the following message before starting: "The necessary VPN sub-system is not available. You will not be able to make a connection to the remote IPSec server." Then the client starts up, but, as one might expect, I can't connect to anything.
After some research, I checked to make sure the the "Cisco Systems, Inc. VPN Service" was started. It wasn't. So, after starting it, I tried again -- same error message. Additionally, the service had died.
After some more research, I set the log capturing to the highest level, and tried again. Here's what I did:
Re: "The necessary VPN sub-system is not available. . ." Error
I agree. Follow the following instructions:
Trying to run the VPN Client returns the following error.
"The necessary VPN sub-system is not available. You will not be able to make a connection to the remote IPSec server."
This may be due to a problem during the installation of the VPN Client where is exited prematurely without error. As a result some of the necessary VPN Client services/drivers do not get started after rebooting.
To see if you have this problem, perform the following steps:
Step 1 Uninstall the VPN Client, restart the PC.
Step 2 Look in the Startup group for the following shortcut:
c:\Documents and Setting\All users\Start Menu\Programs\Startup\Cisco Systems VPN Client.lnk
Step 3 If the link exists, delete it and reinstall the VPN Client. Reinstalling should now fully complete the VPN Client install and it should run properly
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