Microsoft has released Hotfix Update (HU) for:
Exchange Server Subscription Edition (SE)
HU is available for the following specific version of Exchange Server:
Exchange SE RTM
The May...
Updated May 08, 2026
Version 2.0
Blog Post
In the article here:
Update Your Exchange SE Hybrid On-premises Rich Coexistence to Graph | Microsoft Community Hub
It says:
- Stage 2: deprecation of EWS calls and switch to REST-based Microsoft Graph API calls for Exchange hybrid. This is the stage that we are in now. Please note that not all rich coexistence scenarios are fully supported yet and not every cloud environment might support Graph API hybrid calls yet (please see https://learn.microsoft.com/Exchange/hybrid-deployment/deploy-dedicated-hybrid-app#configure-graph-api-permissions).
So if not all rich coexistence scenarios are fully supported yet -- do you anticipate a future Hotfix and/or script update that we'll also need to install/run for full implementation? I'm just wondering if we'll install this Hotfix and then X weeks later, you release the definitive hotfix and we have to install that out of band also?
Nino_Bilic
Microsoft
MicrosoftOur expectation is that if you do install this HU now and run the script, that in the future update, you will not have to re-run the script but rather just install the future update that will finalize on-premises functionality.
In other words - if you run the script to switch to Graph now, installation of (future update) would simply enable the currently missing functionality gap and you would not need to re-run the script.