Microsoft pop-up scam: is that security warning real?

Yes — this is a scam. Microsoft's error and warning messages never include a phone number — a pop-up that gives you one to call is always a scam.

Other versions you might get: A full-screen browser lock, a loud alarm sound with a robotic voice, a fake “Windows Defender” or “Microsoft Support” chat window, or a call claiming to be from Microsoft about a virus or an expiring licence. Whatever the wrapper, the ask is to call, install remote-access software, or pay for “support.”

What to do right now

1. Don't call the number or tap anything in the pop-up. No genuine Microsoft warning tells you to call.
2. Close the browser. If the page won't let you, force-close it (on Windows press Ctrl+Shift+Esc, pick the browser, and End task), then reopen without restoring the session.
3. If you already called or gave remote access: disconnect from the internet, uninstall any app they installed, run a scan with the built-in Windows Security, and change your passwords from another device. Call your bank if you paid or shared card details.
4. Report it. File at reportfraud.ftc.gov, and read Microsoft's own guide to tech-support scams.

How to make sure it never bites you

These pop-ups arrive through malicious ads and redirects, not because your PC is actually infected. Keep Windows and your browser updated, use a content blocker, and never install “support” tools from a pop-up. More on locking things down: protect yourself.