Thanks all for the input, there's a couple of things there that I haven't tried yet. But it is proving a real pain to get rid of. I tried blocking it in google chrome and also deleting it from extensions etc, but every time I delete it from "manage search engines" it's back again the next time I boot and again keeps showing 4 cookies even though I delete them every time.

I did try one program called Spyhunter and it did find it but then wanted a lot of dollars to wipe it and I wasn't sure whether after buying it that it would actually work. Has anyone used this because if it really works then it might be worthwhile investing in it.