If you have Cisco VPN Client installed in Windows 8.1, you are likely receiving a “Failed to Enable Virtual Adapter” error when trying to connect. This fix should resolve the issue.
Open Registry Editor – Right click on the “Start” button in the bottom left corner of the desktop mode. – Select “Run”. Type “regedit” in the run window, and click “ok” (Alternately, you can press the “Windows” key on your keyboard, then type “regedit”. Regedit should appear on the left.) Navigate to the Cisco VPN Client registry key – In registry editor, navigate to the following location: HKLMSystemCurrentControlSetServicesCVirtA
Check the “DisplayName” Key – In the right pane, double click on the “DisplayName” key. It should read “Cisco Systems VPN Adapter” for 32 bit systems, or “Cisco Systems VPN Adapter for 64-bit Windows” for 64 bit systems. If it says anything else, copy/paste the correct info in to the key. – Click “OK”.
Reboot the PC
Verify that Cisco VPN Client is Able to Connect