ScamSplain

Fake Blue-Screen / 'Call This Number' Lock

A webpage fakes a system crash or 'locked' screen with alarms and a phone number, so you call scam 'support' and hand over money or access.

Think a message like this reached you? You can check it right now.

What this scam is

A malicious webpage takes over your screen with a fake Windows crash or a 'your computer has been locked' warning, sometimes with a loud alarm sound and a phone number to call 'Microsoft support.' It is just a web page designed to look like a system failure. Calling connects you to scammers who ask for payment or remote access. Real system errors never give you a phone number to call.

What it usually looks like

  • A full-screen blue error or 'locked' warning in your browser.
  • An alarm sound and a 'do not restart' message.
  • A phone number for 'Microsoft support.'
  • The screen resists closing.

Common warning signs

  • Real errors do not display a support phone number.
  • Alarm sounds and 'call now' urgency.
  • The alert is inside a browser window.
  • You are told not to restart or close it.

Example wording scammers use

** Windows Security Alert ** Your computer has been locked due to suspicious activity. Call 1-8XX-XXX-XXXX immediately. Do not restart.
Error 0x80070570 — contact Microsoft Support now to prevent data loss.

These are illustrative examples written by ScamSplain, not real messages.

What the scammers want

  • You to call and hand over money or remote access.
  • Fear so you do not simply close the page.
  • Gift-card or card payments for 'repair.'

What to do

  • Do not call the number.
  • Close the browser (force-quit it if needed) or restart the computer.
  • Clear the browser or reopen without restoring tabs.
  • Run a security scan for peace of mind.

What to do if you already responded

  • If you called and gave access, disconnect and run a security scan; change key passwords from a clean device.
  • Contact your bank/gift-card issuer if you paid.
  • Report at reportfraud.ftc.gov.

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