BA5108: Error accessing or unlocking the BitLocker-encrypted drive¶
| Error code | Product | Applies to |
|---|---|---|
| BA5108 | BackupAssist | For BackupAssist 8.4.1 or later. |
Description¶
BackupAssist can back up to a BitLocker-encrypted destination drive, unlocking the drive before the backup using the configured key. BA5108 is recorded when BackupAssist could not access or unlock the BitLocker-encrypted destination, so the backup could not proceed.
Common causes:
- The USB drive or volume that holds the BitLocker external/recovery key is not connected, or has been assigned a different drive letter.
- The recovery/external key does not match the destination drive - for example the wrong disk in a rotated set is connected.
- The drive cannot be unlocked with the configured method.
Resolution¶
Resolution 1 - Confirm the BitLocker key and destination drive (recommended)¶
- Make sure the USB volume that holds the BitLocker key is connected before the backup runs.
- Confirm the external/recovery key matches the destination drive for this run.
- Try to unlock the drive manually in Windows (BitLocker Drive Encryption control panel, or "manage-bde -unlock" from an elevated command prompt) to confirm the key and drive are correct.
- Re-run the backup.
Resolution 2 - Check rotated media¶
If you rotate BitLocker-encrypted drives, ensure the correct disk for this run is connected and that its key is available to BackupAssist.
Resolution 3 - Contact technical support¶
If the drive still cannot be unlocked, generate diagnostics and contact support - BackupAssist Support page.
Note on the backup report¶
The backup report shows: Error accessing or unlocking the Bitlocker-encrypted drive.
| Last updated | Created | Further assistance |
|---|---|---|
| 7th Aug 2026 | 7th Aug 2026 | BackupAssist Support page |