When backing up a virtual machine that has more then one VMDK file of the same name in the same folder, on a single datastore, the backup will fail with the errors.
Final error: 0xe0009585 - Unable to open a disk of the virtual machine.
Final error category: Resource Errors
V-79-57344-38277 - Unable to open a disk of the virtual machine.
VixDiskLib_Open() reported the error: You do not have access rights to this file
1. Backup the virtual machine as if it were a physical machine via RAWS.
2. Rename one of the VMDK files to a different name.
3. Move one of the VMDK files to a different datastore.
This issue occurs in Backup Exec 2010 and Backup Exec 2010 R2 and Backup Exec 2010 R3
Example VM with disks of the same name.
VM Name: Test-Machine
Note: Since ESX is a Linux based OS, files with the same name but different capitalization are possible.
If both of these VMDK files are in the same folder the backup will fail with the above error message.