I have used adwcleaner, and some other programs but did not help. I successfully removed it manually from ie and firefox according to the instructions found on many websites, but nothing about opera. I'm using Opera 24.0. i tried to delete the files from appdata/local/, I've deleted the cookies .. didn't help.

so, did somebody found out how can it be removed from opera browser. because there are guides to remove istartsurf from the other browsers.