Someone who signs in with a PIN or fingerprint every day may rarely type their account password. That becomes important when troubleshooting in Safe Mode: Microsoft states that PIN and biometric sign-in options are unavailable there, so a supported account password is needed.

Do not treat this as evidence that your everyday PIN has been changed or that the keyboard has failed. First identify whether the account is local or linked to a Microsoft account. Keep passwords private, and confirm account recovery access before moving into a troubleshooting environment.

Prepare while normal Windows works

Save open work and make sure you have a current backup of important files. Check that you can use the correct password through the normal sign-in options where available. A successful website login can confirm an online account password, but it is not a complete test of the Windows sign-in path or its network state.

Have your device-encryption recovery information available through your own secure records if recovery tools request it. Do not publish that information in a support screenshot. On a managed computer, involve the organisation's administrator rather than trying account workarounds.

Microsoft's sign-in guide describes entering Startup Settings through Shift while selecting Restart, followed by Troubleshoot and Advanced options. Use that documented, temporary route when it fits the problem; avoid changing persistent boot configuration just to experiment.

Make one purposeful comparison

Decide what Safe Mode is meant to test before starting. Record whether you can sign in and whether the specific symptom appears. Reduced drivers and services change the environment, so a working session does not mean every normal Windows component is healthy.

Return to normal startup when the test is finished. If you cannot supply the required password, resolve legitimate account access first rather than repeatedly rebooting into a mode you cannot use. Resetting Windows solely because a PIN is unavailable can create far more work than the original problem.

Reference: Microsoft Support.