Is This Microsoft Message Real? Fake Warnings, Real Defender Alerts and What To Do

A warning on your screen claims your PC is infected, or Windows Security reports a threat it found. These pages put the fake warnings and the real alerts side by side, show the exact signs that separate them, and give the one safe step for each. If you are not sure which you have, start with the five-question checker.

All articles in this cluster

• Real or Fake Warning Checker: Answer 5 Questions
• 'Windows Detected ZEUS Virus': That Pop-Up Is Fake
• 'Call Microsoft Support' at This Number: Microsoft Never Does This
• Fake Blue Screen With a Phone Number: Close It, Don't Call It
• 'Your Computer Was Locked for Illegal Activity': A Scam Script, Word for Word
• Defender Says 'Threat Found': Trojan:Win32 Explained in Plain English
• 'Severe Threat' in Windows Security: What Quarantine Does and Doesn't Do
• Someone Already Remote-Accessed Your PC: The First Hour Checklist
• The 'Microsoft Refund' Call: Why a Stranger Wants to Pay You Back
• Website Pop-Ups Pretending to Be Virus Alerts: Notification Spam