Virus not detected

Hello. I have some form of a virus on my computer that is causing random ads to pop up on my internet browser and is making it very hard to use.

I recently bought Norton antivirus and ran a full system scan along with the power eraser. After this did not seem to find the infection I tried using the free trial of ByteFence anti-malware that was already on my computer and it found a high risk "Browser Search Hijack".

As I do not want to spend the money on a second antivirus software I am wondering how I can remove this risk through Norton.

Thanks in advance for any help.  

*** This is the info ByteFence gave me and Norton couldn't find.

DETECTION NAME: Browser Search Hijack (Chrome)

RISK: High

LOCATION: Warning, Chrome search hijacked to ask.com!