I'd get back to the forums specific to your version vmware to see if they have a fix.
Backups with diff often fail because a file is in use. But that's so common and widely discussed that I'll stop here.
Backup Policy: vmware type with GRT, Weekly = Full , Daily = Diff
Sometimes has backed up failed on Diff backup(never failed on full backup) with different virtual machine.
Quiesce snapshot by manually is successful.
Next time backup is succssful.
Do you have solution?

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