How do I get rid of this pop-up?

I attach a screenshot of pop-up that turns up every time I open Comodo Dragon. After I installed the Hola extention on Comodo Dragon, and selected the USA as the source of TV shows I wanted to watch, my Comodo Dragon browser started swimming in malicious pop-ups and adverts with background voice support that I could not switch off. I uninstalled Hola, uninstalled CD, then re-installed the latter, but I still get the pop-up I attach here.

How do I get rid of it? Or should I ask this question at another section of this Comodo forum? Where do I ask such a question?

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Try scanning with Malwarebytes Antimalware, Super Antispyware and Adwcleaner and see if they can remove it.

Question ! I know your response is correct but I ask if the correct response would not be more and more in 2015, to verify DNS first ?