The Cisco VPN client v5.0 does not work out-of-the-box on Windows 7 and 8. Starting the VPN will result in an error:
This is because of a malfunctioning installer, creating an invalid connection to the Cisco VPN Adapter. To resolve, follow the steps below.
For other versions, the key name in services may not be CVirtA. Certain users on the internet have reported the name to be vpnva.
This method has been verified to work on version 5.0.07.0440 on Windows 8 x64.