A security solution that detects identity-based threats and suspicious activities in on-premises Active Directory environments
The phone number shown in the “Windows Defender” lock screen is part of a tech support scam, not legitimate Microsoft support.
Key points based on Microsoft guidance:
- Genuine Microsoft error or warning messages never include a phone number to call.
- Microsoft does not make unsolicited calls or display phone numbers in pop‑ups to offer to fix a device.
- Pop‑ups that lock the browser or screen and demand a call to “Windows/Microsoft support” are a known scam pattern. They often falsely claim to be from Microsoft Defender or Windows Defender.
- If a screen like this appears again, close the browser (Alt+F4) or use Ctrl+Alt+Del → Task Manager and end the browser process. Do not call the number, do not give remote access, and do not provide payment or personal information.
- If there was any interaction (remote access granted, software installed, or payment made), immediately contact a trusted local technician or official Microsoft Support, change passwords from a clean device, and contact financial institutions if payment details were shared.
- The incident can be reported to Microsoft at https://www.microsoft.com/reportascam and, if needed, to local law enforcement.
References:
- Protect yourself from tech support scams
- Avoid and report Microsoft technical support scams
- Protect yourself from online scams and attacks
- Tech support scams
- My computer was locked by Microsoft defender, I was asked to call 1-844-452-2441 to get it unblocked. Could somebody confirm that this is a legitimated Microsoft number rather than a scammer? - Microsoft Q&A
- Microsoft Defender Scam or Do I have a virus on my computer - Microsoft Q&A
- Windows defender scam - Microsoft Q&A
- Who do I call for support? - Microsoft Q&A