Delegated Mailbox not visible in outlook 2016 but is visible in owa access.


Hello folks,

We have a strange issue here in outlook client 2016.

We have completed the cross forest migration of user mailboxes but facing some issue on the delegated mailbox and shared mailbox.

User A has delegation on the user B, full mailbox rights are assigned and it opens perfectly on the OWA, but delegated Mailbox not visible in outlook 2016.

Both the mailboxes are opening perfectly on OWA and also on the outlook client.

Appreciate your quick reply.

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Accepted answer
  1. Andy David - MVP 145.1K Reputation points MVP

    Remove the full mailbox permission and add it back:

    Remove-MailboxPermission -Identity <Mailbox > -User <Delegated User> -AccessRights FullAccess

    then add back explicitly with automapping in Outlook:

    Add-MailboxPermission -Identity <Mailbox> -User <Delegated User> -AccessRights FullAccess

    It should show up after about 30 minutes in Outlook.

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  1. Eric Yin-MSFT 4,386 Reputation points

    Have you tried re-add the permission as Andy posts?
    You can also try swtiching to online mode and re-creating the profile, see if the issue solved.
    Just for test, if you assign full access permission to another new-created mailbox, does the delegated mailbox shown in the new mailbox's Outlook?

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