In Windows 11/10 and TPM 2.0 now, the BitLocker PIN length was increased to 6 characters. Also, the TPM 2.0 lockout period is greater than the default when a PIN is changed.

Input the BitLocker recovery key. Wait until the unlock period expires, and then enter the correct PIN. Reinstall the operating system, and then reset the TPM chip.

BitLocker locked me out of my PC after a system update, but the recovery key saved me. I found it on my Microsoft account under the device’s details and used it to unlock each encrypted drive.