You can configure a shared mailbox as an alias for UserA and UserB and then synchornize this email alias using the synchonization tool. After synchronization, when UserA signs in to the EUC via SSO. they can manage both their own quarantined emails and those in the shared mailbox. This is the same for UserB when it signs in to the EUC via SSO.
Step 1
Add the shared mailbox as an alias to the user. The procedure differs slightly depending on which Active Directory (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.
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Then modify the clientconf.xml in the Directory Synchronization Tool installation directory. Append the new attribute name into XML node <config> -> <default> -> <emailAliases> -> <emailAttr>.
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For Azure AD:
"Alternate email" should be used as the alias attribute.
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Then modify the clientconf.xml in the Directory Synchronization Tool installation directory. Append the new attribute name into XML node <config> -> <AAD> -> <emailAttr>.
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Step 2
Synchronize the latest email alias to Trend Micro Email Security using the synchronization tool and make sure that the alias has been synchronized by exporting email aliases from the admin console to verify.
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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.
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Step 4
After the above configurations, we can verify that userA can manage the mails from both its own and shared mailbox.
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