If the PC is offline, Windows can require the last password that was used on that device. Changing the Microsoft account password online does not help until the device can connect and sync.
Try these steps:
- On the sign-in screen, connect the laptop to Wi-Fi or Ethernet if that option is available.
- If sign-in still fails, restart into Safe Mode with Networking:
- On the sign-in screen, select Power > Restart.
- When the sign-in screen appears, hold Shift while selecting Power > Restart.
- After the PC restarts to Choose an option, select Troubleshoot > Advanced options > Startup Settings > Restart.
- After restart, press 5 or F5 for Safe Mode with Networking.
- In Safe Mode, try signing in with the password instead of a PIN, because PIN and biometric sign-in are unavailable in Safe Mode.
- If there is another account on the device, try signing in with that account from the lower-left corner of the sign-in screen. After signing in, check for updates and review the accounts on the PC.
- If the account is a Microsoft personal account and the password itself needs to be reset again, use Forgot password? on the Microsoft account sign-in page, or use the sign-in helper tool if no verification options are available.
For Windows 8 specifically, there is also a known issue on domain-joined computers where logon can stop responding after an administrator changes the password. In that case, Microsoft provides a hotfix for Windows 8.
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