Pop-up alerts claiming you have to download this or that software to "stay safe" which can only be closed by force by closing the browser from the task manager.
Random new-tab Ads,
Random redirects upon goodle search, to random search engines.
So far I've tried:
Look for new unknown plugins intalled in the browsers - don't see any.
To uninstall any suspicious software - can't find any.
To look for suspicious processes running in the background - didn't find any.
Scanning my computer with Avast and Malwarebytes, they don't find anything.
Any suggestions would be greatly appreciated.