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Based on your description, the blue BitLocker recovery screen indicates that Windows is unable to automatically unlock the encrypted drive and requires the 48-digit BitLocker recovery key to regain access. This may occur after certain hardware, firmware, or security-related changes.
If the computer does not appear under the Microsoft account you checked, it is possible that the recovery key was backed up to a different account when BitLocker or Device Encryption was enabled. For example, if someone else originally set up the computer or enabled BitLocker, the recovery key may be associated with that person's Microsoft account. If the device was previously connected to a work or school organization, the recovery key may instead be stored with that organization.
Please note that Microsoft Support cannot retrieve, provide, or recreate a lost BitLocker recovery key.
I recommend checking for the recovery key as follows:
- On the BitLocker recovery screen, note the first 8 digits of the Recovery Key ID.
- From another device, open the Microsoft BitLocker recovery-key page: My Recovery Key
- Sign in with the Microsoft account that may have been used when the computer was originally set up or when BitLocker was enabled.
- If recovery keys are listed, compare the Key ID with the one displayed on the BitLocker recovery screen.
- If you find a matching Key ID, enter its corresponding 48-digit recovery key on the affected computer to unlock the drive.
If this computer was previously connected to a work or school organization, please contact that organization's IT administrator, as the recovery key may have been saved with the organization's device record.
If you cannot locate a matching recovery key after checking the accounts associated with the device, unfortunately, there is no supported method to bypass BitLocker and access the encrypted data. This is an intentional security feature of BitLocker that protects the data from being accessed without the required recovery information.
In that situation, the remaining option is to reset the device to make it usable again. However, resetting the device will remove the files stored on the BitLocker-encrypted drive and will not recover the encrypted data. For this reason, I strongly recommend completing the recovery-key search before resetting or reinstalling Windows.
I hope this explanation helps clarify why the recovery key is required and what you can check before considering a reset
Reference: Find your BitLocker recovery key | Microsoft Support
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