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AshJor's avatar
AshJor
Copper Contributor
May 02, 2025

Decommissioning Last Hybrid Exchange Server – All Mailboxes in Cloud, Still Using AAD Connect

Hi all, We're currently running a hybrid Exchange environment with AAD Connect in place. All user mailboxes have already been fully migrated to Exchange Online, and Exchange Online is handling all m...
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Moustafa-Sherif's avatar
Moustafa-Sherif
Copper Contributor
May 06, 2025

Hi AshJor

If you still have synced users from on-premise active directory you should keep at least one Exchange server to be able to edit Exchange attribute on on-premise active directory.

For your information synced objects in Entra ID cannot be modified from Azure portal , you can modify it only from on-premise Exchange server or active directory.

For more information please read this Microsoft article:

https://learn.microsoft.com/en-us/exchange/decommission-on-premises-exchange#why-you-may-not-want-to-decommission-exchange-servers-from-on-premises

Andres-Bohren's avatar
Andres-Bohren
Iron Contributor
May 06, 2025

Hi Moustafa-Sherif​ 
With Exchange 2019 CU12 you can use Recipient Management and don't need Exchange Server anymore

https://learn.microsoft.com/en-us/exchange/manage-hybrid-exchange-recipients-with-management-tools

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