Error Code [91:163] Unable to create a virtual machine snapshot of [ ]. [ ] Please check the virtual machine snapshot tree.

Virtual Machine snapshot backup fails.

Symptoms

Log files contain an entry similar to:

Error: 91:163 Unable to create a virtual machine snapshot of [^1%s]. [^2%s] Please check the virtual machine snapshot tree. It may be necessary to upgrade/reinstall the VMware tools on the virtual machine. Please consult http://kb.vmware.com/kb/1009073 for additional information. job id: [ ]

Causes

Possible causes:

• Unsupported vSphere version.
• Virtual Machine is on a different vCenter tree.
• An attempt was made to backup an unsupported entity. SCSI controllers engaged in bus sharing are not supported for backup. See documentation.
• VMWare was unable to create a snapshot as a number of old snapshots were still present.

Resolution

• Check documentation for supported vSphere versions.
• Check and clear vSphere client for any old unnecessary snapshots.
• For unsupported entities, you may need to use a File System iDataAgent to backup the VM.

It may be necessary to upgrade/reinstall the VMware tools on the virtual machine. Please consult VMware KB for additional information.