Microsoft has released a critical update for Windows Defender to resolve a persistent bug causing false security alerts. Users reported frequent notifications claiming that antivirus protection was disabled, despite the software running correctly in the background.
The issue primarily affected devices running Windows 10 and Windows 11. On these systems, the security center failed to accurately synchronize status data with the underlying security interfaces, leading to incorrect warnings even when real-time protection was active.
The company confirmed that the error was not caused by malware but by a synchronization logic flaw triggered after system service restarts or updates. This discrepancy also caused status inconsistencies for users who had installed third-party security software.
To address the bug, Microsoft has deployed a patch via standard security updates and a Defender engine update. The company advises all users to check the Windows Update settings to download and install the latest definitions and security patches to restore correct functionality.
