Users in a hybrid deployment can’t access a shared mailbox that was created in Exchange Online [Resolved]
-
Date: 24/04/2018 10 minutes to read
Applies to: Exchange Online, Exchange Server 2016, Enterprise Edition, Exchange Server 2016, Standard Edition, Exchange Server 2013 Enterprise Exchange
CAUSE
These issues can occur when the shared mailbox is created by using the Exchange Online management tools. In this situation, the on-premises Exchange environment has no object to reference for the shared mailbox. Therefore, all queries for that SMTP address fail.
Microsoft SOLUTION
The following is the Microsoft solution
Which is workaround not a solution because the azure sync isn’t replicating both ways it replicates one way from on-prem to online
So the workaround is to create the same ExchangeGuid property on the new on-premises object to match the cloud mailbox
Move it back to online this way you will have the SMTP both ways
On GAL and OAB for both users online and on-Prem for more details go to the following:
It is useful sometimes
Another solution
I think it is a very good one
Is creating the online shared mailbox it must be @yourdomain.onmicrosoft.com Then add a contact on your prem which will point to the online shared mailbox
This way both users will be able to see the account also send mail to the shared online mailbox, the only cons for this is that you will receive duplicate SMTP address warning in the office 365
GAL AND OAB will be both updated
Note:
GAL Is syncing from the Global catalog if you aren’t using cache mode OAB is used by online and cached users
First, try to create it using the admin center portal
https://outlook.office365.com/ecp
Create the shared mailbox must be
@yourdomain.onmicrosoft.com as primary
Then go to you
Exchange admin center on-prem
Open contacts start creating mail contact with external SMTP
Create new contact choose alias you want and display name this will appear for both on-prem and online
Add the external email address of the shared mailbox which will match the one you have created on the admins center for online shared mailbox
Then go to you Azure ad connect server
Open the azure ad module for windows power shell as admin
Ru the following command
Start-ADSyncSyncCycle -PolicyType Delta
Then open the synchronization service
Go to operations
Make sure the updates are there
You will have the following error in the admin center you can ignore it
Just telling you that you have duplicate SMTP and this is something you know because you are the creator