Unable to get rid of Safe Finder

My laptop has the browser hijacker virus and I had to keep removing this extension called Interactive speed to get rid of it every few days. It redirected all my google searches to yahoo search and involved this dodgy logo called Safe Finder. I was sick of having to remove the extension every now and the, so I found used Combo Cleaner to delete the interactive speed app altogether. It was fine for a few days, but the browser redirecting problem has cropped up again. I checked my extensions, but there are none. So I have no way to get rid of this problem even temporarily. It's a huge hassle and a security threat.

Please help me.