For a few weeks, my browser (Chrome) will open itself up, and then continue opening up a new window every 3-5 minutes. These are blank windows, not even an "about: blank" in the URL window. Not new tabs--new Chrome windows. So I have to shut them down one by one, and have to turn off my computer when I'm away or I come back to many open browser windows. I've run newly updated Malwarebytes and three different antivirus programs, Registry Mechanic, CC Cleaner, scanned with Norton 360, reinstalled Chrome. Nothing works. Help!

Install and try Firefox (Mozilla) to see if the same thing happens. If not, then you might uninstall Chrome. Yeah, a PITA for sure, but if something has installed a bad plugin (or infected one), and you can't figure out what it is, then that may be your only recourse.

it could be some cookies activated by some virus, so run antivirus scanning could solve the poblem

A virus like that does really make i annoying.