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BitLocker recovery guide: format & spacing edits

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As reported in issue ticket #8460 (Wrong section), there are a couple of 
sections where the last line of a bullet list has merged with a following 
paragraph due to missing whitespace or insufficient line breaks.

This pull request should mitigate those issues.

Thanks to Eddddeee for reporting the document issue(s).

Additional changes:

- doubled the number of blank lines before each new heading (H2, H3, H4)
- squashed double or triple spacing in bullet point list and numbered lists
- added an inferred colon at the end of a handful of paragraph/section headings

Closes #8460
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Trond B. Krokli
2020-10-14 22:32:45 +02:00
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windows/security/information-protection/bitlocker/bitlocker-recovery-guide-plan.md
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@ -20,7 +20,7 @@ ms.custom: bitlocker
# BitLocker recovery guide
**Applies to**
**Applies to:**
- Windows 10
@ -32,6 +32,7 @@ This article assumes that you understand how to set up AD DS to back up BitLock
This article does not detail how to configure AD DS to store the BitLocker recovery information.
## <a href="" id="bkmk-whatisrecovery"></a>What is BitLocker recovery?
BitLocker recovery is the process by which you can restore access to a BitLocker-protected drive in the event that you cannot unlock the drive normally. In a recovery scenario, you have the following options to restore access to the drive:
@ -40,6 +41,7 @@ BitLocker recovery is the process by which you can restore access to a BitLocker
- A data recovery agent can use their credentials to unlock the drive. If the drive is an operating system drive, the drive must be mounted as a data drive on another computer for the data recovery agent to unlock it.
- A domain administrator can obtain the recovery password from AD DS and use it to unlock the drive. Storing recovery passwords in AD DS is recommended to provide a way for IT professionals to be able to obtain recovery passwords for drives in their organization if needed. This method requires that you have enabled this recovery method in the BitLocker Group Policy setting **Choose how BitLocker-protected operating system drives can be recovered** located at **Computer Configuration\\Administrative Templates\\Windows Components\\BitLocker Drive Encryption\\Operating System Drives** in the Local Group Policy Editor. For more information, see [BitLocker Group Policy settings](bitlocker-group-policy-settings.md).
### What causes BitLocker recovery?
The following list provides examples of specific events that will cause BitLocker to enter recovery mode when attempting to start the operating system drive:
@ -95,18 +97,19 @@ If software maintenance requires the computer be restarted and you are using two
Recovery has been described within the context of unplanned or undesired behavior, but you can also cause recovery as an intended production scenario, in order to manage access control. For example, when you redeploy desktop or laptop computers to other departments or employees in your enterprise, you can force BitLocker into recovery before the computer is given to a new user.
## <a href="" id="bkmk-testingrecovery"></a>Testing recovery
Before you create a thorough BitLocker recovery process, we recommend that you test how the recovery process works for both end users (people who call your helpdesk for the recovery password) and administrators (people who help the end user get the recovery password). The –forcerecovery command of manage-bde is an easy way for you to step through the recovery process before your users encounter a recovery situation.
**To force a recovery for the local computer**
**To force a recovery for the local computer:**
1. Click the **Start** button, type **cmd** in the **Start Search** box, right-click **cmd.exe**, and then click **Run as administrator**.
2. At the command prompt, type the following command and then press ENTER:
`manage-bde -forcerecovery <BitLockerVolume>`
**To force recovery for a remote computer**
**To force recovery for a remote computer:**
1. On the Start screen, type **cmd.exe**, and then click **Run as administrator**.
2. At the command prompt, type the following command and then press ENTER:
@ -115,6 +118,7 @@ Before you create a thorough BitLocker recovery process, we recommend that you t
> [!NOTE]
> Recovery triggered by `-forcerecovery` persists for multiple restarts until a TPM protector is added or protection is suspended by the user. When using Modern Standby devices (such as Surface devices), the `-forcerecovery` option is not recommended because BitLocker will have to be unlocked and disabled manually from the WinRE environment before the OS can boot up again. For more information, see [BitLocker Troubleshooting: Continuous reboot loop with BitLocker recovery on a slate device](https://social.technet.microsoft.com/wiki/contents/articles/18671.bitlocker-troubleshooting-continuous-reboot-loop-with-bitlocker-recovery-on-a-slate-device.aspx).
## <a href="" id="bkmk-planningrecovery"></a>Planning your recovery process
When planning the BitLocker recovery process, first consult your organization's current best practices for recovering sensitive information. For example: How does your enterprise handle lost Windows passwords? How does your organization perform smart card PIN resets? You can use these best practices and related resources (people and tools) to help formulate a BitLocker recovery model.
@ -134,10 +138,12 @@ When you determine your recovery process, you should:
- [Post-recovery analysis](#bkmk-planningpostrecovery)
### <a href="" id="bkmk-selfrecovery"></a>Self-recovery
In some cases, users might have the recovery password in a printout or a USB flash drive and can perform self-recovery. We recommend that your organization create a policy for self-recovery. If self-recovery includes using a password or recovery key stored on a USB flash drive, the users should be warned not to store the USB flash drive in the same place as the PC, especially during travel, for example if both the PC and the recovery items are in the same bag it would be very easy for access to be gained to the PC by an unauthorized user. Another policy to consider is having users contact the Helpdesk before or after performing self-recovery so that the root cause can be identified.
### <a href="" id="bkmk-recoveryretrieval"></a>Recovery password retrieval
If the user does not have a recovery password in a printout or on a USB flash drive, the user will need to be able to retrieve the recovery password from an online source. If the PC is a member of a domain the recovery password can be backed up to AD DS. However, this does not happen by default, you must have configured the appropriate Group Policy settings before BitLocker was enabled on the PC. BitLocker Group Policy settings can be found in the Local Group Policy Editor or the Group Policy Management Console (GPMC) under **Computer Configuration\\Administrative Templates\\Windows Components\\BitLocker Drive Encryption**. The following policy settings define the recovery methods that can be used to restore access to a BitLocker-protected drive if an authentication method fails or is unable to be used.
@ -145,6 +151,7 @@ If the user does not have a recovery password in a printout or on a USB flash dr
- **Choose how BitLocker-protected operating system drives can be recovered**
- **Choose how BitLocker-protected fixed drives can be recovered**
- **Choose how BitLocker-protected removable drives can be recovered**
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 Active Directory Domain Services (AD DS). Select the **Do not enable BitLocker until recovery information is stored in AD
DS** check box if you want to prevent users from enabling BitLocker unless the computer is connected to the domain and the backup of BitLocker recovery information for the drive to AD DS succeeds.
@ -161,18 +168,22 @@ You can use the following list as a template for creating your own recovery proc
- [Gather information to determine why recovery occurred](#bkmk-gatherinfo)
- [Give the user the recovery password](#bkmk-givepassword)
### <a href="" id="bkmk-recordcomputername"></a>Record the name of the user's computer
You can use the name of the user's computer to locate the recovery password in AD DS. If the user does not know the name of the computer, ask the user to read the first word of the **Drive Label** in the **BitLocker Drive Encryption Password Entry** user interface. This is the computer name when BitLocker was enabled and is probably the current name of the computer.
### <a href="" id="bkmk-verifyidentity"></a>Verify the user's identity
You should verify that the person that is asking for the recovery password is truly the authorized user of that computer. You may also wish to verify that the computer with the name the user provided belongs to the user.
### <a href="" id="bkmk-locatepassword"></a>Locate the recovery password in AD DS
Locate the Computer object with the matching name in AD DS. Because Computer object names are listed in the AD DS global catalog, you should be able to locate the object even if you have a multi-domain forest.
### Multiple recovery passwords
If multiple recovery passwords are stored under a computer object in AD DS, the name of the BitLocker recovery information object includes the date that the password was created.
@ -181,10 +192,12 @@ If at any time you are unsure what password to provide, or if you think you migh
Since the password ID is a unique value that is associated with each recovery password stored in AD DS, running a query using this ID will find the correct password to unlock the encrypted volume.
### <a href="" id="bkmk-gatherinfo"></a>Gather information to determine why recovery occurred
Before you give the user the recovery password, you should gather any information that will help determine why the recovery was needed, in order to analyze the root cause during the post-recovery analysis. For more info about post-recovery analysis, see [Post-recovery analysis](#bkmk-planningpostrecovery).
### <a href="" id="bkmk-givepassword"></a>Give the user the recovery password
Because the recovery password is 48 digits long the user may need to record the password by writing it down or typing it on a different computer. If you are using MBAM, the recovery password will be regenerated after it is recovered from the MBAM database to avoid the security risks associated with an uncontrolled password.
@ -192,6 +205,7 @@ Because the recovery password is 48 digits long the user may need to record the
> [!NOTE]
> Because the 48-digit recovery password is long and contains a combination of digits, the user might mishear or mistype the password. The boot-time recovery console uses built-in checksum numbers to detect input errors in each 6-digit block of the 48-digit recovery password, and offers the user the opportunity to correct such errors.
### <a href="" id="bkmk-planningpostrecovery"></a>Post-recovery analysis
When a volume is unlocked using a recovery password, an event is written to the event log and the platform validation measurements are reset in the TPM to match the current configuration. Unlocking the volume means that the encryption key has been released and is ready for on-the-fly encryption
@ -202,6 +216,7 @@ If you notice that a computer is having repeated recovery password unlocks, you
- [Determine the root cause of the recovery](#bkmk-determinecause)
- [Refresh BitLocker protection](#bkmk-refreshprotection)
### <a href="" id="bkmk-determinecause"></a>Determine the root cause of the recovery
If a user needed to recover the drive, it is important to determine the root cause that initiated the recovery as soon as possible. Properly analyzing the state of the computer and detecting tampering may reveal threats that have broader implications for enterprise security.
@ -219,6 +234,7 @@ Review and answer the following questions for your organization:
To help you answer these questions, use the BitLocker command-line tool to view the current configuration and protection mode (for example, **manage-bde -status**). Scan the event log to find events that help indicate why recovery was initiated (for example, if boot file change occurred). Both of these capabilities can be performed remotely.
### <a href="" id="bkmk-refreshprotection"></a>Resolve the root cause
After you have identified what caused recovery, you can reset BitLocker protection and avoid recovery on every startup.
@ -231,6 +247,8 @@ The details of this reset can vary according to the root cause of the recovery.
- [Unknown PIN](#bkmk-unknownpin)
- [Lost startup key](#bkmk-loststartup)
- [Changes to boot files](#bkmk-changebootknown)
### <a href="" id="bkmk-unknownpin"></a>Unknown PIN
If a user has forgotten the PIN, you must reset the PIN while you are logged on to the computer in order to prevent BitLocker from initiating recovery each time the computer is restarted.
@ -244,6 +262,7 @@ If a user has forgotten the PIN, you must reset the PIN while you are logged on
3. In the PIN reset dialog, provide and confirm the new PIN to use and then click **Finish**.
3. You will use the new PIN the next time you unlock the drive.
### <a href="" id="bkmk-loststartup"></a>Lost startup key
If you have lost the USB flash drive that contains the startup key, then you must unlock the drive by using the recovery key and then create a new startup key.
@ -254,18 +273,22 @@ If you have lost the USB flash drive that contains the startup key, then you mus
2. Open Manage BitLocker.
3. Click **Duplicate start up key**, insert the clean USB drive on which you are going to write the key and then click **Save**.
### <a href="" id="bkmk-changebootknown"></a>Changes to boot files
This error might occur if you updated the firmware. As a best practice you should suspend BitLocker before making changes the firmware and then resume protection after the update has completed. This prevents the computer from going into recovery mode. However if changes were made when BitLocker protection was on you can simply log on to the computer using the recovery password and the platform validation profile will be updated so that recovery will not occur the next time.
## Windows RE and BitLocker Device Encryption
Windows Recovery Environment (RE) can be used to recover access to a drive protected by [BitLocker Device Encryption](bitlocker-device-encryption-overview-windows-10.md). If a PC is unable to boot after two failures, Startup Repair will automatically start. When Startup Repair is launched automatically due to boot failures, it will only execute operating system and driver file repairs, provided that the boot logs or any available crash dump point to a specific corrupted file. In Windows 8.1 and later, devices that include firmware to support specific TPM measurements for PCR\[7\] the TPM can validate that Windows RE is a trusted operating environment and will unlock any BitLocker-protected drives if Windows RE has not been modified. If the Windows RE environment has been modified, for example the TPM has been disabled, the drives will stay locked until the BitLocker recovery key is provided. If Startup Repair is not able to be run automatically from the PC and instead Windows RE is manually started from a repair disk, the BitLocker recovery key must be provided to unlock the BitLocker–protected drives.
## BitLocker recovery screen
During BitLocker recovery, Windows can display a custom recovery message and hints that identify where a key can be retrieved from. These improvements can help a user during BitLocker recovery.
### Custom recovery message
BitLocker Group Policy settings in Windows 10, version 1511, let you configure a custom recovery message and URL on the BitLocker recovery screen, which can include the address of the BitLocker self-service recovery portal, the IT internal website, or a phone number for support.
@ -281,6 +304,7 @@ Example of customized recovery screen:
![Customized BitLocker Recovery Screen](./images/bl-password-hint1.png)
### BitLocker recovery key hints
BitLocker metadata has been enhanced in Windows 10, version 1903 to include information about when and where the BitLocker recovery key was backed up. This information is not exposed through the UI or any public API. It is used solely by the BitLocker recovery screen in the form of hints to help a user locate a volume's recovery key. Hints are displayed on the recovery screen and refer to the location where key has been saved. Hints are displayed in both the modern (blue) and legacy (black) recovery screen. This applies to both the bootmanager recovery screen and the WinRE unlock screen.
@ -302,6 +326,7 @@ There are rules governing which hint is shown during the recovery (in order of p
8. There is no specific hint for keys saved to an on-premises Active Directory. In this case, a custom message (if configured) or a generic message, "Contact your organization's help desk," will be displayed.
9. If two recovery keys are present on the disk, but only one has been successfully backed up, the system will ask for a key that has been backed up, even if another key is newer.
#### Example 1 (single recovery key with single backup)
| Custom URL | Yes |
@ -316,6 +341,7 @@ There are rules governing which hint is shown during the recovery (in order of p
![Example 1 of Customized BitLocker recovery screen](./images/rp-example1.PNG)
#### Example 2 (single recovery key with single backup)
| Custom URL | Yes |
@ -330,6 +356,7 @@ There are rules governing which hint is shown during the recovery (in order of p
![Example 2 of customized BitLocker recovery screen](./images/rp-example2.PNG)
#### Example 3 (single recovery key with multiple backups)
| Custom URL | No |
@ -344,6 +371,7 @@ There are rules governing which hint is shown during the recovery (in order of p
![Example 3 of customized BitLocker recovery screen](./images/rp-example3.PNG)
#### Example 4 (multiple recovery passwords)
| Custom URL | No |
@ -373,6 +401,7 @@ There are rules governing which hint is shown during the recovery (in order of p
![Example 4 of customized BitLocker recovery screen](./images/rp-example4.PNG)
#### Example 5 (multiple recovery passwords)
| Custom URL | No |
@ -402,10 +431,12 @@ There are rules governing which hint is shown during the recovery (in order of p
![Example 5 of customized BitLocker recovery screen](./images/rp-example5.PNG)
## <a href="" id="bkmk-usingaddrecovery"></a>Using additional recovery information
Besides the 48-digit BitLocker recovery password, other types of recovery information are stored in Active Directory. This section describes how this additional information can be used.
### BitLocker key package
If the recovery methods discussed earlier in this document do not unlock the volume, you can use the BitLocker Repair tool to decrypt the volume at the block level. The tool uses the BitLocker key package to help recover encrypted data from severely damaged drives. You can then use this recovered data to salvage encrypted data, even after the correct recovery password has failed to unlock the damaged volume. We recommend that you still save the recovery password. A key package cannot be used without the corresponding recovery password.
@ -415,6 +446,7 @@ If the recovery methods discussed earlier in this document do not unlock the vol
The BitLocker key package is not saved by default. To save the package along with the recovery password in AD DS you must select the **Backup recovery password and key package** option in the Group Policy settings that control the recovery method. You can also export the key package from a working volume. For more details on how to export key packages, see [Retrieving the BitLocker Key Package](#bkmk-appendixc).
## <a href="" id="bkmk-appendixb"></a>Resetting recovery passwords
You should invalidate a recovery password after it has been provided and used. It should also be done when you intentionally want to invalidate an existing recovery password for any reason.
@ -424,7 +456,7 @@ You can reset the recovery password in two ways:
- **Use manage-bde** You can use manage-bde to remove the old recovery password and add a new recovery password. The procedure identifies the command and the syntax for this method.
- **Run a script** You can run a script to reset the password without decrypting the volume. The sample script in the procedure illustrates this functionality. The sample script creates a new recovery password and invalidates all other passwords.
**To reset a recovery password using manage-bde**
**To reset a recovery password using manage-bde:**
1. Remove the previous recovery password
@ -453,7 +485,7 @@ You can reset the recovery password in two ways:
> [!WARNING]
> You must include the braces in the ID string.
**To run the sample recovery password script**
**To run the sample recovery password script:**
1. Save the following sample script in a VBScript file. For example: ResetPassword.vbs.
2. At the command prompt, type a command similar to the following:
@ -466,7 +498,7 @@ You can reset the recovery password in two ways:
> [!NOTE]
> To manage a remote computer, you can specify the remote computer name rather than the local computer name.
You can use the following sample script to create a VBScript file to reset the recovery passwords.
You can use the following sample script to create a VBScript file to reset the recovery passwords:
```vb
' Target drive letter
@ -539,6 +571,7 @@ WScript.Echo "A new recovery password has been added. Old passwords have been re
'WScript.Echo "Type ""manage-bde -protectors -get " & strDriveLetter & " -type recoverypassword"" to view existing passwords."
```
## <a href="" id="bkmk-appendixc"></a>Retrieving the BitLocker key package
You can use two methods to retrieve the key package, as described in [Using Additional Recovery Information](#bkmk-usingaddrecovery):
@ -548,14 +581,14 @@ You can use two methods to retrieve the key package, as described in [Using Addi
The following sample script exports all previously-saved key packages from AD DS.
**To run the sample key package retrieval script**
**To run the sample key package retrieval script:**
1. Save the following sample script in a VBScript file. For example: GetBitLockerKeyPackageADDS.vbs.
2. At the command prompt, type a command similar to the following:
**cscript GetBitLockerKeyPackageADDS.vbs -?**
You can use the following sample script to create a VBScript file to retrieve the BitLocker key package from AD DS.
You can use the following sample script to create a VBScript file to retrieve the BitLocker key package from AD DS:
```vb
' --------------------------------------------------------------------------------
@ -697,7 +730,7 @@ WScript.Quit
The following sample script exports a new key package from an unlocked, encrypted volume.
**To run the sample key package retrieval script**
**To run the sample key package retrieval script:**
1. Save the following sample script in a VBScript file. For example: GetBitLockerKeyPackage.vbs
2. Open an administrator command prompt, type a command similar to the following:
@ -882,6 +915,7 @@ Function BinaryToString(Binary)
End Function
```
## See also
- [BitLocker overview](bitlocker-overview.md)