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Restore the Master Boot Record

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The Master Boot Record (MBR) is the first sector of the boot disk. It is the part of the hard drive that tells the operating system what to boot and where to boot from.

  • The DETech (Standalone) boot disk.

  • The USB memory stick containing the recovery information file (.xml); this must be plugged in before booting from the DETech (Standalone) boot disk.

  • A system authorized with the authorization code.

When Drive Encryption activates, a backup of the Windows MBR is sent up to the server for use in recovery scenarios, and can be exported from ePO - On-prem in the Recovery Information file (.xml).

This feature allows you to deactivate Drive Encryption on a manually decrypted boot disk by restoring the Windows MBR (preserving the in-situ partition table) to the disk. Do not use this feature on secondary (non-boot) disks.

Caution

This feature should only be used on a boot disk where the data is not encrypted. Performing this operation on an encrypted boot disk renders the system non-bootable.

  1. Make a sector level backup of the drive being processed.

  2. Manually decrypt the disk using the Crypt Sectors feature.

  3. Boot the system with the DETech (Standalone) boot disk to load the Trellix DETech interface.

  4. Enter the daily authorization code, then confirm the authorization status.

  5. Authenticate with a Token or Recovery Information File (.xml), then confirm the authentication status.

  6. Under Disk Operations, click Restore MBR.

  7. In the Restore MBR dialog box, select the MBR that you want to use for the restore operation (Original MBR or Drive Encryption MBR), then click OK.

    You can select or deselect the Keep the current Partition Table as needed.

  8. When prompted to confirm that you want to overwrite the MBR, click OK.

    If you select Original MBR, the MBR is replaced with the one that was present on the disk before Drive Encryption was activated.