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Microsoft fixes known issue causing Windows Defender crashes
August 18, 2026
Back to all postsRecently, Microsoft identified and released a fix for a known issue causing Windows Defender, their built-in antivirus software, to crash on certain Windows systems. This issue affected Windows 10 and 11, particularly versions 20H2, 21H1, and 21H2, and was triggered by a specific XML file. The crash led to Windows Defender becoming ineffective at protecting devices, potentially exposing systems to security risks. As a result, this issue poses a significant threat to Canadian businesses, especially Small and Medium-sized Enterprises (SMBs) that rely on Windows Defender for cybersecurity protection.
For Canadian businesses, this incident underscores the importance of maintaining up-to-date software to ensure adequate cybersecurity protection. It is recommended that all Windows users apply the latest updates provided by Microsoft to resolve the issue and safeguard their systems.
Source: BleepingComputer
microsoftwindows defendercybersecuritysoftware updatesmb
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