Hi Elena, you are dealing with a GoSaveNow adware, to eliminate it you must first uninstall several programs which re-installs this adware to one's Internet browsers. At time of testing it installed several programs to Control Panel - "Gosavvenow", "YoutubEAdBloCke", "GS_Booster" and "GS_Sustainer". In your case the names of programs in Control Panel could be a bit different - nevertheless you should uninstall all recently installed suspicious applications. Then I would recommend restarting your computer and removing unwanted plugins from your Internet browsers. After this procedure you should also scan your computer with Malwarebytes Antimalware and Spyhunter - both are capable of detecting and removing this adware.