A pop-up locks your screen with a loud warning, or the phone rings and someone says they're from Microsoft. Either way, your first instinct is panic — your files, your photos, your bank logins. But real tech companies do not detect your viruses for you and then call to tell you about it. This is always a scam.
"Microsoft Windows Defender: 5 viruses detected on your PC. Call this number immediately for remote support: 1-888-555-0165"
Why this scam works
The pop-up is designed to feel unclosable — a full-screen browser alert with a fake countdown or a system alarm sound. Panic pushes people to call the number before they stop to think. Once you call, the "technician" walks you into installing remote-access software like TeamViewer or AnyDesk — and now they're inside your computer, not fixing it.
5 signs it's fake
- They contacted you first — Microsoft, Apple, and antivirus companies don't call or pop up unsolicited warnings
- You can't close it normally — a real error lets you close the tab; this one fills the screen and blocks the X
- Asks for remote access — TeamViewer, AnyDesk, or "let me screen-share" is the actual attack, not the fix
- Wants payment by gift card or wire — for a "support fee" or "license renewal"
- Caller ID looks local or toll-free — spoofed to seem legitimate
What to do instead
- Do not call the number or click anything in the pop-up
- Close it via Task Manager (Windows) or Force Quit (Mac) — not the fake "X" button
- If you already gave remote access, disconnect from the internet and run a real antivirus scan, then change your passwords from a different device
- Paste the message or call transcript into ScamCheck for a free risk score