Microsoft Defender message scam

Question

I have been receiving pop up messages that Microsoft Defender is locking down my computer and requesting that I call a number to unlock. I called the number but quickly realized that it was a scam... I would like to stop getting the message

Answer 1

The pop-up and phone number are part of a tech support scam, not a real Microsoft Defender message. Real Microsoft error or warning messages never include a phone number and Microsoft does not cold call or ask to be called to fix a device.

To stop and avoid these messages:

1. Close the fake “lock” screen
   • Press Ctrl + Alt + Del.
   • Open Task Manager.
   • End all browser processes (for example, Microsoft Edge, Chrome, or other browsers) to close the scam page.
2. Do not call any numbers from pop-ups
   • Ignore and close any message that:
     • Shows a phone number to call for Microsoft or Windows support.
     • Claims Microsoft Defender has locked the computer and demands a call.
   • Microsoft support messages never include a phone number and Microsoft does not send unsolicited emails or make unsolicited calls to fix a computer.
3. Protect the device from future scam pop-ups
   • Use Microsoft Edge as the browser when possible. It uses Microsoft Defender SmartScreen to block known support scam sites and can stop pop-up dialog loops.
   • Keep Microsoft Defender Antivirus enabled and up to date, and install all Windows security updates.
   • Download software only from official Microsoft partner sites or the Microsoft Store; avoid third‑party download sites that may bundle scam malware.
4. If any information was given to the scammers
   • Uninstall any applications they asked to install and consider resetting the device to factory state if unsure what was changed.
   • Run a full scan with Microsoft Defender Antivirus and apply all security updates.
   • Change passwords and monitor sign-in activity and financial accounts if any payment or sensitive information was provided.
5. Report the scam
   • Report the attempted tech support scam to Microsoft at www.microsoft.com/reportascam.
   • Unsafe or phishing websites can also be reported using the Report an unsafe site form.

Following these steps will stop the current pop-up, reduce the chance of seeing similar scams again, and help protect the device and accounts.

---

References:

• Avoid and report Microsoft technical support scams
• Tech support scams
• Protect yourself from online scams and attacks
• Protect yourself from tech support scams
• Microsoft Defender Scam or Do I have a virus on my computer - Microsoft Q&A
• Windows defender scam - Microsoft Q&A
• I WAS HACKED - Microsoft Q&A
• Who do I call for support? - Microsoft Q&A

AI-generated content may be incorrect. Read our transparency notes for more information.

Answer 2

Hi Bob,

Reboot the PC and then run a scan

with MalwareBytes Free to make sure

there is no virus.