Post Hotfix 216746 Granular Restore Technology (GRT) enabled AVVI Incremental backups to a Deduplication Storage Folder is failing with error "0xe0009585 - Unable to open a disk of the virtual machine"
A hotfix is now available for this issue in the current version(s) of the product(s) mentioned in this article. Refer to the Hotfix link under Related Documents at the end of this article to obtain the hotfix needed to resolve the issue.
Backup Exec 2012 Rev 1798 Hotfix (217347).
NOTE: AVVI VMware Agent FULL backups must be re-run installing Hotfix 217347.