On 06/16/2014 my computer suddenly shut down on it's own. I was probably on facebook or something. When I restarted it, Avast (free version) started sending alerts every few seconds, "Threat has been detected." I have run several scans since then with Avast and found nothing. I ran a scan with Malwarebytes free version, and it found nothing. Yet Avast still keeps sending popups saying "threat has been detected." Its getting really annoying. Also, I uninstalled and re-installed Avast, but still getting massive alerts. I have silenced it for now, but I use this computer for work and I am worried.
Any help is greatly appreciated.
Thanks so much,