# Windows 11: What to Do When Microsoft Defender’s Quick Scan Won’t Run

Is Microsoft Defender's Quick Scan on Windows 11 refusing to start, or halting before it's done? Start by making sure you're opening it from the correct spot in Windows Security. If the problem continues, reboot your PC, shut down any other antivirus software that's active, and install Defender's ne

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| Published | 2 October 2026 |

Source: https://egamers.io/windows-11-what-to-do-when-microsoft-defenders-quick-scan-wont-run/