Object with reference was not found in hierarchy cache

Veeam Backup & Replication
6.x, 7.x, 8.x, 9.x
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Task fails with the error message, “Task failed Error: Object with reference '<moref>' was not found in hierarchy cache”

This issue can be confirmed by editing the job, navigating to "Virtual Machines" and clicking the [Recalculate] button. VM's whose RefID have changed will report as having a "0 B" size.

Note: Older version of Veeam Backup & Replication may report the error as "Task failed Error: Object <vmname> not found"


This error is caused by the VM’s unique inventory reference identification number (MOREF, or Managed Object Reference) changing within the virtual infrastructure, or the VM having been deleted. Veeam is still attempting to find the VM by its old reference ID number based on a “find vm by NAME where REFID = X” query.

Note: The most common events that cause a VM MOREF ID to change are:

  • Reinstallation or creation of a new vCenter server where the old VC database is not reused.
  • A VM is removed from inventory and then added back to inventory.
  • In rare cases a host crash, which prompts the host to be removed and added back to the VC may cause the VMs on that host get new MOREF IDs.




  1. Rescan the vCenter Servers
    1. Navigate to [Backup Infrastructure]
    2. Expand [Managed Servers]>[VMware vSphere]
    3. Right-Click on [vCenter Servers] and select [Rescan]
  2. Re-add the VM to the Job
    1. Edit the Job
    2. Navigate to the Virtual Machines tab.
    3. Select the VM whose MoRef has changed.
    4. Click Remove
    5. Click Add...
    6. Click Refresh*
    7. Add the VM removed in step 4.
    8. Click [Finish] to save the Job settings.


*Veeam Backup & Replication caches infrastructure information to improve performance, the refresh function purges the cached data. The refresh function must be used when resolving this issue.

Validate Resolution

Resolution can be confirmed without running the job. Edit the job, navigating to "Virtual Machines" and click the [Recalculate] button. Note that the VM's whose MoRefs changed now report as having the correct size.

Important Note

Please be aware that VM's are tracked by their unique MoRef ID. When the MoRef changes the VM is considered an entirely different VM. As such Veeam Backup & Replication will treat them accordingly and create a Full restore point for the "new" VM.

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