question

Hello @BrandonRobinson-0896 Sorry for the inconvenience this must have caused!

You mentioned that you are backing up 3 VMs using MARS agent and it failing with "SalBitmapError".

This issue could happen due to multiple reason.

Cause 1: Due to old backup agent, ensure the VM has the latest backup agent installed.

Cause 2: Due to the metadata iteration. When the MARS agent is iterating over the metadata vhd's file folder and if there is any directory corrupt or some file system issue then this error can come.

Mitigation steps:

• If the VM has outdated backup agent then update the agent by following the steps mentioned in the document [Done]
  

• Removed Anti-Virus [Done]
  .
  

• Retry the backup operation. Usually retry operation resolves this issues if the issue still persist then try the next step.
  

• Resync it by adding the below regkey.
  

• Open the Registry editor by typing regedit in the Run window.
  

• Go to Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows Azure Backup\Config\CloudBackupProvider path.
  

• Right-click on the right side window and add a new string value ResyncNeeded_<ReplicaID>.
  

• Once the value is added right-click on the value name and click Modify
  

• Add the value data 1 and click Ok.

  Registry Key:

Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows Azure Backup\Config\CloudBackupProvider
ResyncNeeded_<ReplicaID>=dword:1

Sample registry with ReplicaID:

Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows Azure Backup\Config\CloudBackupProvider
ResyncNeeded_bbbbbbbb-cccc-bbbb-cccc-bbbbbbbbbbbb=dword:1

Note: Here the guid bbbbbbbb-cccc-bbbb-cccc-bbbbbbbbbbbb is replica id. You can find it in CBEngine logs from (C:\Program Files\Microsoft Azure Recovery Services Agent\Temp). Sample log with ReplicaSnapshotId is given below:

CBpDsVolumeInfo::FindMatchingVolumeContext VolumeContext not found for ReplicaId [{bbbbbbbb-cccc-bbbb-cccc-bbbbbbbbbbbb}] , ReplicaSnapshotId [{00000000-0000-0000-0000-000000000000}] , Volume [\\?\Volume{c0d59d8f-0000-0000-0000-100000000000}]

• As the metadata vhd is on the scratch space there could be storage issue. To check if the backup is failed due to scratch storage issue perform the below:
  

• From the CBP trace log check the error code, if log contains error code 0x80070057 (Parameter Invalid) or 0x80070035 (Network path not found) then this is possibly storage issue.
  

• Check the VHDMP, NTFS, System/VSS events to verify this cause.
  

• If there is any storage issue, you need to resolve this issue first and retry the backup operation.

Hope this helps!

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