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Is it possible to use Office365 (Specifically Outlook365) with on prem Exchange Server 2019. I recall that in order for this to work a few years ago it required a registry hack.
I have a client that has recently upgraded their entire tech (Server 2019 and Exchange 2019) and were using Office 2019. Their CRM vendor has just dropped support for any version of office other than 365, and the client is understandably livid. The now after a few months of use drop their Office 2019 Pro for Office 365.
Is it purely the Autodiscover that is required or is OLK365 hardwired to connect to M365?
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Hi @Shane King ,
As Andy says, outlook365 will use direct connect first, and if it doesn't work, it will uses Autodiscover.There is a related post and the Autodiscover process you can refer to:
https://answers.microsoft.com/en-us/outlook_com/forum/all/exchange-2019-outlook-not-working-in-outlook-365/abe6b1e7-5637-43d0-9bfd-f16f1bb5ec9f
You can mark useful replies as answers to help more people.
Hi, I'm here to confirm with you if your issue has been resolved. If the problem is successfully solved, you can share your solution and mark them or the helpful reply as answer, this will make answer searching in the forum easier and be beneficial to other community members as well.
Outlook 365 will use direct connect and try to connect to M365 first if you have a presence in M365. If you do not have a presence, it will use autodiscover to find an endpoint next.
You can change this behavior if you are seeing any issues
https://www.slipstick.com/office-365/directconnect-office-365/