Had to uninstall Comodo in order to install and use Cisco Client VPN

I’ve been using Comodo Personal Firewall for a long time and now I have someone with a Cisco VPN and after installing the Cisco VPN client and making a connection I get a blue screen.

OS: Windows XP (latest patches)
CPU: Core 2 Duo

The only fix was uninstalling Comodo ( I tried just disabling it but that didn’t work)

Is there a fix for this or at least a reason?

Cisco VPN has bits of Zonealarm in. It is possible to remove them