A BitLocker recovery key cannot be generated, recreated, or retrieved by Microsoft Support if it was never backed up or can’t be found. The only way to unlock the drive is with the existing 48-digit recovery key.
Check these locations using another device:
- On the BitLocker recovery screen, note the first 8 digits of the recovery key ID.
- Check the Microsoft account recovery key page and sign in with each Microsoft account that might have been used on that PC. Match the key ID to the device key.
- If the PC was ever signed into a work or school account, check the work or school account Devices page and select View BitLocker Keys.
- Check for a printed copy of the key.
- Check any USB flash drive where the key may have been saved.
- If someone else set up the device or enabled BitLocker, the key might be in that person’s Microsoft account.
If the device is managed by an organization, contact that organization’s IT support.
If the recovery key cannot be found, the remaining option is to reset or reinstall Windows using Windows recovery options. Warning: this removes all files on the device.
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