Views:
You can configure a shared mailbox as the alias to the userA and userB and then synchronize this email alias by using the synchronization tool. After that when single sign-on (sso) to the End User Console (EUC) with the userA you can manage the quarantined mails of userA and the shared mailbox and when sso to the EUC with the userB you can managed the quarantined mails of userB and shared mailbox.

Step 1
Add the shared mailbox as an alias to the user. The procedure differs slightly depending on which AD is in use.
See the screenshots below for both Microsoft AD and Azure AD.


For Microsoft AD:
"postalAddress" should be used as the alias attribute. 

image.png

Then modify the clientconf.xml in the Directory Synchronization Tool installation directory. Append the new attribute name into XML node <config> -> <default> -> <emailAliases> -> <emailAttr>.

image.png

For Azure AD:
"Alternate email" should be used as the alias attribute.

Then modify the clientconf.xml in the Directory Synchronization Tool installation directory. Append the new attribute name into XML node <config> -> <AAD> -> <emailAttr>.


Step 2
Synchronize the latest email alias to TMEMS using the synchronization tool and make sure the alias has been synchronized by exporting email aliases from the admin console to verify.



Step 3
Set up single-sign-on of end user in the admin console and make sure the new attribute was not in the "Identity claim type" item.


Step 4
After the above configurations we can verify that userA can manage the mails from its own and shared mailbox.



NOTE:
For concerns about the approve/blocked sender list of shared mailbox.
UserA and userB can jointly manage the approved and blocked sender list of shared mailbox.
That's means, if userA adds an approved sender for the shared mailbox, userB can view and edit this approved sender.