Hi Paul Chou,
Thank you for sharing the release notes for Windows 11 Insider Experimental Preview Build 26340.9882.
Based on the Windows Hello section of that document, the behavior you described appears to be expected. Although Windows now lets you use whichever available sign-in method responds first, the same documentation specifically notes that a PIN may still be required first at certain times, such as after a restart. Once that initial PIN authentication is completed, biometric sign-in should work normally for subsequent unlocks.
This also explains why fingerprint recognition works when your device wakes from sleep but is unavailable immediately after a startup or restart. Since the fingerprint reader continues to work after sleep, this does not currently suggest a problem with the sensor or fingerprint enrollment.
If fingerprint sign-in remains unavailable even after the initial PIN sign-in, that would indicate a different issue. Otherwise, you may submit feedback through Feedback Hub if you believe the wording or sign-in prompt could be clearer, especially since this is an Experimental Insider build and changes may still be adjusted. Thank you so much for your understanding.
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