No error is returned to users, however the 0kb attachment in .eml format cannot be opened, essentially the Enterprise Vault retrieve does not work.
In order to view the archived item use the option 'Restore from Vault' or search the item using the 'Enterprise Vault Search' both available in the EV for Mac Client floating bar.
The root cause is unknown
This issue is currently under investigation by Veritas Technologies LLC. Pending the outcome of the investigation, this issue may be resolved by way of a patch or hotfix in current or future revisions of the software. However, this particular issue is not currently scheduled for any release. If you feel this issue has a direct business impact for you and your continued use of the product, please contact your Veritas Sales representative or the Veritas Sales group to discuss these concerns.
Note: Customers experiencing this issue are encouraged to contact Veritas Technical Support as data is still being collected to assist in resolving this issue.