We are getting errors when creating Shared Mailboxes in Exchange 2016

Question

We are getting errors when creating Shared Mailboxes in our Exchange 2016 On-Premise Server. When we try creating a shared mailbox and add the permission to another user at the same time it gives error i.e. Couldn't resolve the user or group. If the user or group is a foreign forest principal, you must have either a two-way trust or an outgoing trust. If we cancel the mailbox will sill be created without the permission. Another thing observed that if we create a shared mailbox without adding user permission and assign the permissions later, it works just fine, however, this is creating additional work for the ServiceDesk as they are having go back into the mailbox to add the users.

We have a multi-domain scenario. Our parent organization holds the exchange organization and the Exchange servers are installed on the child domain. We did checked the trust relationship which looks good.

Answer 1

Please check this thread for your help - https://community.spiceworks.com/topic/2251303-unable-to-add-user-to-a-distribution-group-with-send-as-permissions

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