Exchange Administration Center (Exchange 2016 on-premise) not showing some mailboxes

Question

We have recently migrate a Exchange 2010 to a Exchange 2016 (on-premise). The migration process was succesfull but some weeks after finish this migration we have detected that some mailboxes aren't visible from the list showed by th Exchange Administration Center. Indeed, we have a total of 440 mailboxes but EAC show only 376 mailboxes.

In other hand, we can manage this "hidden" mailboxes through EMS with no problem and, if we execute some scripts to control the total amount of mailboxes we can see them. In addition, this mailboxes ara completly operative.

We have followed the solution showed here https://social.technet.microsoft.com/Forums/en-US/25bd106f-1d51-4cfb-afac-657d569c4efc/recovered-mailbox-not-showing-in-ecp-but-it-works?forum=exchangesvradmin but these mailboxes aren't yet visible from EAC.

Have anybody any idea how to fix this?

Thanks in advance

Answer 1

Yes, if they are shared, then you wont see them under the Mailboxes menu, but you will under Recipients/Shared

To Convert:

 Get-Mailbox <SampleUserYoucantSeeinEAC> | set-mailbox -Type Regular

To convert all of them in bulk

Get-Mailbox -RecipientTypeDetails Shared | Set-Mailbox -Type Regular

After that you will be able to see them in EAC under Mailboxes

Answer 2

What are the recipient types of the ones you can't see?

Get-Mailbox <SampleUserYoucantSeeinEAC>  |FL *recipienttype*