Update 6/11/2025: We updated the timeline of this deprecation mentioned in this post.
Exchange Online will permanently remove support for Basic authentication with Client Submission (SMTP AUTH) gra...
Updated Jun 12, 2025
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For applications that do not support OAuth2, HVE would actually be a great alternative. Unfortunately, it often fails because HVE can basically only be used as a noreply@.
It would be great if you could reply to an email sent via HVE.
Either because you can set a forwarding from the HVE address to another mailbox (tested with Mail Flow Rule not possible) or SendAs from another mailbox for the HVE account is made possible.
Any of this on the roadmap?
Simone_Liebal
Microsoft
Microsoftjohndfe36540 Great feedback, thank you! We are actively working on Reply-To functionality for HVE!
SendAs is something we're currently looking into as a future improvement. If you have any additional feedback on your use cases for SendAs, I'd love to hear more :)!
Hello,
Could you clarify something for me that I received on a MS Support ticket. I was told that HVE will not be an option for basic auth as even with HVE, OAUTH/Modern Auth needs to be used. Is this correct? Will all other MS alternatives like Azure Comm Services and HVE require OAUTH only after September?
Thank you,
Simone_LiebalThank you for the answer!
An important use case for some of my customers would be the following.
For example, my customer uses a SaaS application which has to send mails from their domain to internal and external recipients. The public IP of the service is shared by several customers, which is why an inbound connector or SPF with the IP is not an option. SMTP OAuth2 is not supported by the service. So HVE with basic auth. would be perfect as long as there is some way to reply to the sent mail.Many applications do not support specifying a reply-to address. Therefore, in this case the reply-to address should be modifiable by EXO/HVE. Is it planned that way?
- Simone_Liebal
johndfe36540 Thank you for sharing more about your / your customers' use case!
We're still in the process of finalizing the details for this feature, however the ability to define the Reply-To address on service side is one of the aspects we want to solve for, as we are aware that there are applications that don't have an easy option to do so on client side.
