Microsoft Defender Offline

Run Microsoft Defender Offline if:

Windows Security (named Windows Defender Security Center in previous versions of Windows) detects rootkits or other highly persistent malware on your PC and alerts you to use Microsoft Defender Offline. You might see a message stating that malware was found on your device, or receive a message in Windows Security notifying you that additional cleaning is required.

You suspect your PC might have malware that's hiding on it, but your security software doesn’t detect anything. In this situation, you can start a Microsoft Defender Offline scan from Windows Security settings. Here's how: