Hi Adrian Jones,
I’m sorry you’re running into this, especially since the same sign-in problem comes back each time the Preview update is installed. The fact that you can sign in normally again after removing the update in Safe Mode is an important clue.
To help narrow this down, could you please let us know:
- What is the exact “not supported” message you see on the sign-in screen? A screenshot would also be helpful, as long as it does not contain any personal information.
- Which sign-in methods have you tried, such as PIN, password, fingerprint or other Windows Hello options?
- What is the name or KB number of the update shown under Settings > Windows Update > Update history?
- Which Windows Insider channel is the device currently enrolled in under Settings > Windows Update > Windows Insider Program?
In the meantime, since removing the Preview update restores sign-in, I would avoid reinstalling that same update repeatedly until we have a better idea of what is triggering the issue.
If you can access Windows normally after uninstalling the update, you can also open Feedback Hub and report the behavior there. Please include the build number, the exact sign-in error, and the steps that reproduce the problem. This is particularly useful for issues that occur on Insider Preview builds. Thank you so much for your understanding.
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