Firewall not functioning properly message

I have Comodo Firewall 3.14.13 on Windows XP computer. When the computer boots up and Comodo starts the icon in the tray has a red circle and slash through it and upon opening Comodo the message is “System Startup. Network firwall not functioning properly. Run Diagnostics.” When I run Diagnostics, the message is “The Diagnostics did not find any problems with your installation.” Then I exit Comodo, wait a few seconds and restart Comodo and it works fine. Since Comodo is on the computer for the teenagers and I have a password on Comodo (so they cannot change the settings ;)), if I am not around when they start up the machine, it means that they are surfing the net unprotected.

I have tried uninstalling Comodo and reinstalling it to no avail. Any help would be appreciated.

Have you tried the current v5RC?