Security issue
I was in Safari and was doing a search when I got a message that my computer was compromised. It said to not shut it down and to call Apple Support right away. It gave a 800 number. I shut down my computer and unplugged it.
I assumed it was a scam.
I don’t know what to do next?
How do I know if I have malware on my computer?
How do I get rid of it?
iMac 21.5″, macOS 10.13