Since I had dealt with Microsoft Tech Support a day earlier, I answered when I saw "Microsoft" in the Caller ID. A young(?) man with a heavy accent said he was from Microsoft Support and that there was a problem with my computer. (Not anymore, I thought.) Thinking this might be the well-known scam, I asked, "How do I know you are really from Microsoft?" Instead of giving me a case number, he said he could prove it to me. He then told me what to type in the Run command line. That's when I said he had called at a bad time, and hung up on him.
This is almost certainly a spoofed number for scam purposes. Spoofed, because 619-849-5872 is the number for a Microsoft Store, 7007 Friars Rd., San Diego, CA, but I seriously doubt a store that sells computers, Windows phone, X-box, software, etc. would be calling about a problem. Let's see if he calls back.