How do I get back my uninstalled Comodoantivirus without a backup?

Received the message prompt that support for my version of Comodoantivirus would expire and I needed to install a new version. When I tried, I got the message that I first needed to uninstall the current version. Did that and when I was done, there was no more message prompt for installing the new version. How do I get back the virus protection without a backup of the first version?

Have a read of this,it gives you all the information and links to the new CIS


ps This is only for XP and Vista,will not function on win2000