In April's cumulative updates for Windows 11, Microsoft made changes to Windows Hello facial recognition functionality. These modifications aim to address a vulnerability that could potentially allow attackers to access a victim's computer using spoofed biometric data, though the likelihood of this exploit being used is considered low.

The updated Windows Hello now requires data from a color camera for authentication. Previously, facial recognition authorization could work using only infrared sensor data. Due to these security enhancements, Windows Hello may no longer function in darkness or low-light conditions. Users of some devices like Surface Laptops have already encountered this issue.

As a potential workaround, Microsoft suggests disabling the webcam in Device Manager. This would force Windows Hello to rely solely on infrared sensor data, restoring functionality in dark environments. However, since this would disable the webcam system-wide, other Windows applications would also lose camera access - making this a questionable solution.

Microsoft has stated it doesn't plan to "fix" Windows Hello's dark functionality as it doesn't consider this behavior to be a bug.

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