Free Firewall and Antivirus not working together

I downloaded and installed the free Comodo firewall. It seems to work fine, but I wanted extra protection so I tried to install the Comodo Antivirus. It downloaded, but says it is not compatable with the firewall and I need to remove the firewall before the antivirus can install. Why can’t both run on my Windows XP? The version of the security package you pay for has both on it so why can’t the free versions run? ???

Why don’t you remove the firewall and just download CIS premium ( yes it is free) and install that?

Thanks for the tip. I will do that this evening and post the results. I appreciate the help.