Scancomputer.site pop-ups are originated in your browser by adware currently enabled in your workstation. The purpose of such pop-up windows is not to help you clean your PC, but rather to make you waste your money in favor of cyber frauds who distribute this virus in the web.
Pop-ups from errorhelper.site site are caused by adware. The goal of all these pop-ups is to make users believe that their computers are infected. Finally, after users gets scared, the pop-up tricks them into calling a special toll free number where cyber frauds will offer their absolutely useless services.