Comodo Dragon DNS

Hello, I would like to you ask about this Comodo DNS. I am the user of Comodo Dragon Browser. Yesterday I install software for Internet Security, and it ask me to block Comodo Dragon Browser. But I reject it. Suddenly I can’t use this Comodo DNS on my Comodo Dragon Browser. So, I uninstall the Internet Security. And this Comodo DNS still wont work. Thank you for your help. Sorry for my bad english.

What is happening that you say you can’t use Comodo DNS on Dragon? Do you get an alert or warning?