In a scenario where RMS enabled items with attachments reside in a Public Folder to which the logged on user does not have at least Editor client permissions, the items will fail to display correctly when opened and the error shown in the Error section of this article will be displayed. The problem affects non-archived items as well as archived items.
Enterprise Vault is currently unable to retrieve the original item for this shortcut:
Do you want Enterprise Vault to ignore any other shortcuts?
Temporarily disabling the EV Add-in for Outlook will allow the affected items to be opened without error.
Enterprise Vault 11.0.1 - Release Details