I installed Comodo Security on my lab computers. Now they cannot login to the domain controller. The only way to get Comodo to let me login is to remove the computer from the domain then re-add it then and only then will Comodo let me login. I do not intend to do this on 28 computers.
I called tech support who barely spoke english and told me, they had no idea and maybe I should post a message to the forums. Not much for support.