Ever since we announced our intention to disable Basic Authentication in Exchange Online we said that we would add Modern Auth (OAuth 2.0) support for the IMAP, POP and SMTP AUTH protocols.
Today,...
Updated Jun 30, 2022
Version 6.0
Blog Post
1 MIN READ
Announcing OAuth 2.0 support for IMAP and SMTP AUTH protocols in Exchange Online
Our implementation experience is that with older Exchange accounts the OAuth SMTP authentication works, but with newer accounts it does not, due to an SMTP security flag that is now default to on vs before it was off.
https://answers.microsoft.com/en-us/msoffice/forum/all/office-365-smtp-authentication-failing-even-with/4e2dcfc4-2626-4c3b-a945-9ff1b3404539?page=2
This is a big friction point and blocker for our application. Essentially, customers use OAuth to grant SMTP and IMAP for our application with admin consent (when applicable) and we still can't auth with SMTP. This means we are still forced to have them perform basic auth.
Can you all please prioritize this, we have thousands of Office 365 customers wanting this ability, especially so, given the deadlines on deprecating basic auth (which is understandable).
There will be huge amounts of friction and support if we have to guide customers and their IT staff through obscure settings in the admin ... for which we couldn't even find ... and if we have to explain powershell to our end user customers ... this isn't going to happen. We can't be expected to take on that support. If OAuth SMTP scope grant is given and there is admin consent (when applicable) ... we should be able to authenticate as a delegated app.