VBR: Error during guest credentials test ("Building list of machines to process Error: [...])

  • 5 February 2023

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Just a quick post on an interesting issue with the Guest Credentials test in Veeam Backup & Replication we’ve seen last week. Instantly after clicking “Test Now” in the Guest Processing section of a certain backup job, an error was displayed.

"Building list of machines to process Error: (Child group-vXYZ (Folder) for object XYZ was not found)"

Normally you see such errors with vSphere when a certain object has been deleted or recreated. While Veeam displays names of objects, internally it works with MoRef IDs. So we’ve checked the job selection, custom credentials and the application aware processing settings. But all listed objects were still valid, especially no folders where used anywhere.

We’ve contacted Veeam Support and had a remote session. The support engineer discovered some orphaned VM folders in the exclusions. After removing those, the error disappeared and the credential check worked again. From a logical point I thought those weren’t relevant for the check, so I didn’t check them.

So, if you experience this error and can’t find the cause, better also take a look at the exclusions 😉



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Sometimes there are reasons for problems you would never think of… 😎

Userlevel 7
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Interesting that exclusions would cause this as the test is for the VMs in the job itself.  Nice to see you got it fixed.

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Quoting @Chris.Childerhose I can only say “it’s very strange”. I remember having MoRef errors during vCenter upgrade from 6.7 to 7.0 but never during normal backup process. 

Guest processing credentials are managed by OS account. 

Only for info…. do you rememer which they were the folder in exclusion list? 


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Yeah, funny that an exclusion caused an error...you know...since you were telling it NOT to back that data up.

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@Andanet There were folders of deleted Veeam virtual labs in the exclusions.

@dloseke Absolutley. But thinking it through, the credential tests needs to check the exclusions in order to not test those VMs. So it makes sense that Veeam uses the exclusions at that point, only the message/error could be better or more detailed.