Cisco VPN Client Fails to Install When Maximum Number of Network Filter Drivers Has Been Reached – Error 27850

I had been helping a vendor install Cisco VPN Client and the installation kept failing with “Error 27850.  Unable to manage networking component.  Operating system corruption may be preventing installation.”

As it turns out, there was other VPN software installed and bound to the local network adapter.  Windows 7 has a default maximum number of 8 network filter drivers it can have assigned to the network adapter. 

The image at the following link shows a good example of adding more than 8 network filters to an adapter: https://supportforums.cisco.com/thread/2015629#3067225

The maximum number of filter drivers for Windows 7 can be set to 14.  To increase the value from the default, the change must be done in HKEY_Local_Machine\System\CurrentControlSet\Control\Network\MaxNumFilters.  Increasing the value to 14 allowed the Cisco VPN Client installation to complete.

Networking VPN Cisco Windows 7