After you are, your PC should restart. Microsoft Defender Offline will load and perform a quick scan of your PC in the recovery environment. You'll be prompted that you're about to be signed out of Windows. Select Microsoft Defender Offline scan, and then select Scan now. In older versions of Windows 10: Under T hreat history, select Run a new advanced scan. In an up-to-date version of Windows 10 or Windows 11: Under Current threats, select Scan options. On the Virus & threat protection screen, do one of the following: Select Start, and then select Settings > Update & Security > Windows Security > Virus & threat protection. Save any open files and close all apps and programs. You suspect your PC might have malware hiding on it, but your security software doesn’t detect anything. Windows Security (also called Windows Defender Security Center in previous versions of Windows) detects rootkits or other highly persistent malware on your PC and recommends you use Microsoft Defender Offline. When should I use Microsoft Defender Offline? Microsoft Defender Offline is a powerful offline scanning tool that runs from a trusted environment, without starting your operating system.

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