Bitlocker Recovery Key File Name

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Juvencio Parise

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Aug 3, 2024, 1:45:35 PM8/3/24

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As part of the BitLocker recovery process, it's recommended to determine what caused a device to enter in recovery mode. Root cause analysis might help to prevent the problem from occurring again in the future. For instance, if you determine that an attacker modified a device by obtaining physical access, you can implement new security policies for tracking who has physical presence.

For planned scenarios, such as a known hardware or firmware upgrades, initiating recovery can be avoided by temporarily suspending BitLocker protection. Suspending BitLocker leaves the drive fully encrypted, and the administrator can quickly resume BitLocker protection after the planned task is completed. Using suspend and resume also reseals the encryption key without requiring the entry of the recovery key.

If suspended, BitLocker automatically resumes protection when the device is rebooted, unless a reboot count is specified using PowerShell or the manage-bde.exe command line tool. For more information about suspending BitLocker, review the BitLocker operations guide.

Recovery is described within the context of unplanned or undesired behavior. However, recovery can also be caused as an intended production scenario, for example in order to manage access control. When devices are redeployed to other departments or employees in the organization, BitLocker can be forced into recovery before the device is delivered to a new user.

When Startup Repair is launched automatically due to boot failures, it only executes operating system and driver file repairs, provided that the boot logs or any available crash dump point to a specific corrupted file. On devices that support specific TPM measurements for PCR[7], the TPM validates that Windows RE is a trusted operating environment and unlocks any BitLocker-protected drives if Windows RE has not been modified. If the Windows RE environment has been modified, for example the TPM is disabled, the drives stay locked until the BitLocker recovery key is provided. If Startup Repair can't run automatically, and instead Windows RE is manually started from a repair disk, then the BitLocker recovery key must be provided to unlock the BitLocker-protected drives.

Windows RE will also ask for your BitLocker recovery key when you start a Remove everything reset from Windows RE on a device that uses the TPM + PIN or Password for OS drive protector. If you start BitLocker recovery on a keyboardless device with TPM-only protection, Windows RE, not the boot manager, will ask for the BitLocker recovery key. After you enter the key, you can access Windows RE troubleshooting tools or start Windows normally.

Both the Recovery password and Recovery key can be supplied by users in the Control Panel applet (for data and removable drives), or in the preboot recovery screen. It's recommended to configure policy settings to customize the preboot recovery screen, for example by adding a custom message, URL, and help desk contact information. For more information, review the article BitLocker preboot recovery screen.

Answering the questions helps to determine the best BitLocker recovery process for the organization, and to configure BitLocker policy settings accordingly. For example, if the organization has a process for resetting passwords, a similar process can be used for BitLocker recovery. If users aren't allowed to save or retrieve recovery information, the organization can use a data recovery agents (DRAs), or automatically back up recovery information.

In each of these policies, select Save BitLocker recovery information to Active Directory Domain Services and then choose which BitLocker recovery information to store in AD DS. Use the option Do not enable BitLocker until recovery information is stored in AD DS to prevent users from enabling BitLocker unless the backup of BitLocker recovery information for the drive to Microsoft Entra ID or AD DS succeeds.

To recover BitLocker, a user can use a recovery password, if available. The BitLocker recovery password is unique to the device it was created on, and can be saved in different ways. Depending on the configured policy settings, the recovery password can be:

Having access to the recovery password allows the holder to unlock a BitLocker-protected volume and access all of its data. Therefore, it's important for your organization to establish procedures to control access to recovery passwords and ensure that they're stored securely, separate from the devices they protect.

There's an option for storing the BitLocker recovery key in a user's Microsoft account. The option is available for devices that aren't members of a domain and that the user is using a Microsoft account. Storing the recovery password in a Microsoft account is the default recommended recovery key storage method for devices that aren't Microsoft Entra joined or Active Directory joined.

Backup of the recovery password should be configured before BitLocker is enabled, but can also be done after encryption, as described in the BitLocker operations guide.
The preferred backup methodology in an organization is to automatically store BitLocker recovery information in a central location. Depending on the organization's requirements, the recovery information can be stored in Microsoft Entra ID, AD DS, or file shares.

There's no automatic way to store the recovery key for removable storage devices in Microsoft Entra ID or AD DS. However, you can use PowerShell or the manage.bde.exe command to do so. For more information and examples, review the BitLocker operations guide.

DRAs can be used to recover OS drives, fixed data drives, and removable data drives. However, when used to recover OS drives, the operating system drive must be mounted on another device as a data drive for the DRA to be able to unlock the drive. Data recovery agents are added to the drive when it's encrypted, and can be updated after encryption occurs.

The benefit of using a DRA over password or key recovery is that the DRA acts as a master key for BitLocker. With a DRA you can recover any volume protected by the policy, without having to find a specific password or key for each individual volume.

The BitLocker recovery information for Microsoft Entra joined devices can be stored in Microsoft Entra ID. The advantage of storing the BitLocker recovery passwords in Microsoft Entra ID, is that users can easily retrieve the passwords for the devices assigned to them from the web, without involving the help desk.

The BitLocker recovery password information stored in Microsoft Entra ID is a bitlockerRecoveryKey resource type. The resource can be retrieved from the Microsoft Entra admin center, the Microsoft Intune admin center (for devices enrolled in Microsoft Intune), using PowerShell, or using Microsoft Graph. For more information, see bitlockerRecoveryKey resource type.

The BitLocker recovery information for a device joined to an Active Directory domain can be stored in AD DS. The information is stored in a child object of the computer object itself. Each BitLocker recovery object includes the recovery password and other recovery information. More than one BitLocker recovery object can exist under each computer object, because there can be more than one recovery password associated with a BitLocker-enabled volume.

The BitLocker key package isn't saved by default. To save the package along with the recovery password in AD DS, the Backup recovery password and key package policy setting must be selected in the policy that controls the recovery method. The key package can also be exported from a working volume.

I have an internal hard drive-- my G drive--(Win10) that behaves differently from all my other drives in regards to bitlocker (both internal and portable USB drives). First, I can't do anything through the bitlocker UI in Win10; I have to do things through the manage-bde command line. So I figured out how to get it encrypted via command line by doing this:

I have read in a few places that the '.BEK' is stored on a USB thumb drive. I put in a thumb drive (my OS forced me to encrypt it first with bitlocker to make it writable). I ran the above command again. No file written any place that I can find. No idea where that BEK file exists. Please help.

There is a difference between F:\ and F:: the former refers to the root directory of the F: drive, the latter refers to the current working directory of the F: drive in your current command prompt session.

Since the days of MS-DOS, the DOS/Windows command prompt has remembered one working directory per drive. So, if before running the manage-bde -on command, you had been doing something on the F: drive and had issued a command like:

then using just F: without the backslash would still refer to F:\some\directory\deep\in\the\hierarchy, even if you had switched to a different drive after that. And if you really used just F: without the backslash in the command to enable Bitlocker for drive G:, that's where the recovery key file would have been created.

So, the external key file would have to be on the F: drive, but not necessarily in the root directory of that drive. Or if your F: is a removable drive, the key file would be on the drive that was F: at the time you ran the command to enable BitLocker on G:.

If you have already searched your entire F: drive for *.BEK files and found nothing, it's possible that you have accidentally deleted the recovery key file. If so, then you should create a new recovery key file right now, before you do anything else.

If anything bad happens to your system disk, this single action might be worth all the data you currently have on your G: drive, since without a usable recovery key, the data will be as good as gone if the system disk fails.

Explanation: like several other disk encryption solutions, Bitlocker has a master key that is actually used to encrypt the data on a drive. Changing the master key is a slow and difficult operation as it requires decrypting and re-encrypting the whole drive. So, the user is never allowed to access this master key directly.