Hi Rachel Johnson,
It sounds like Windows may be expecting a different sign-in method than the one you're trying. Since you recently reinstalled Windows 10 Pro, one thing worth checking is whether the account shown on the sign-in screen matches the account that was previously used on the device.
Please try these checking steps:
- On the sign-in screen, select Other user (if available).
- If you previously used a local account, enter the username instead of your email address.
- If you used a Microsoft account, verify that the email address displayed matches the one you expect to use.
- If you recently changed your Microsoft account password, restart the PC and sign in with the current password rather than a PIN.
- If BitLocker recovery is being requested instead of a normal sign-in, locate your recovery key through your Microsoft account or backup records.
If the account shown on the sign-in screen doesn't look familiar, let us know exactly what sign-in options are available and whether you performed an upgrade, reset, or clean installation. That detail can help narrow down the next steps.
I understand how frustrating it can be to be locked out of a system after reinstalling Windows. Hopefully one of the checks above helps identify which account Windows is expecting, and the community will be glad to help further if you can share a screenshot or additional details.
Feel free to ask me by clicking "Add Comment" or "Add Answer" if you cannot add comment so your response will be visible. Thanks for your effort.
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