Pop up said "tech_adware pop.exe" virus was on my computer and was critical, and I must call tech support. It was safari browser on IMac computer. Pop up wouldn’t go away and when I called, caller remote controlled my computer 30 min explaining how dangerous problem might be, then asked for my credit card number to have apple certified level 5 technician fix it and install new firewall. I got his number to call back, which was different than initial, and called family who said macs don’t get viruses and its a scam, so I unplugged computer and keep ignoring calls from 000-000-0000. He said name was "Asheek kumar" I think.