Microsoft Defender is crashing on some PCs, but there is a fix

Microsoft Defender is crashing on some PCs, but there is a fix

By Sean Endicott
Publication Date: 2026-08-19 14:45:00

Microsoft claims that Windows 11’s built-in security tool is enough for most PC users, but that’s only the case if the tool works. An issue affecting some PCs prevents security scans from being completed, leaving systems potentially vulnerable.

The problem was flagged on Reddit by user Huynh_Jovi. Several users in that thread have had issues running scans with Microsoft Defender. Both Full Scan and Quick Scan appear to be affected.