From my understanding if you have at least the catalog object but not the physical mailbox the physical mailbox is automatically created when the process that requires the SA account is called. Because you do not have the directory object I would try to create it manually in adsite then proceed and move a mailbox and see if the SA Mailbox is created. Therefore you can still connect to Exchange through System Attendant but you can not log in Mailbox the item can actually be opened. Over the weekend there was some exchange activity done at the client end on one of the servers and now we dont see the System attendant mailbox (they did re-create the mailbox database) Comment. 1 Comment 1 Solution 3926 Views Last Modified. I have the following questions: 1 How can I check if this mailbox is a gravestone or in that table 2 Where is this table 3 Can I restore this mailbox via a snapshot NetApp Single Mail Restore. Exchange Microsoft 365 Enterprise Windows Server 2008. As stated in Evan blog post see Additional Information Sources there are two components for the Mailbox Systemadendant the directory object and the mailbox. You can change your application to rely on a user-created account and mailbox. You can still use the Mailbox Mailbox Mailbox see Additional Resources for more information about this mailbox. The exception is: : ScriptingAgent: Exceptions are generated when you call the OnComplete API script: An undefined execute user property is used.