Basic Authentication Deprecation in Exchange Online – May 2022 Update

Hey ViliusS 

Thanks for that, yes have seen & had to use the Relay already.

It's really not a great/practical option though, as yes have to get 25 open, & really one doesn't want a site open that way.

Alas, many of our customers put say UPS & Backups out with their staff eg Remote workers, so need to use their app mailers from Home or elsewhere & Connectors for their homes & elsewhere is simply impractical. 

Here's just one example of the issue.

Customer needs to use Outlook with Authenticator challenging launch everytime or not show mail (Medical Privacy) if not authenticated legitimately.

When we setup on 365 for the Customer, with the domain having Security Defaults ON, the customer was over the moon that that worked as desired.

They've had Outlook for years, but NEVER used it because of this, rather they've WebMail accessed their ISP until now..... so 365 & Authenticator = happy customer.

Then, because they have Backup Software (EaseUS ToDo in this case, but almost any other would be similarly afflicted), & they have PowerShield SafeGuard UPS units the NetGuard software also, they need to have ability for those software items to be able to Send Backup Results & UPS alert emails via SMTP mail.

They (like any typcial Small Business customer) won't pay for a dedicated mailbox, & when with ISP they were able to use their existing eMail address creds within the Configs of those apps - no issues. 

With 365, Security Defaults on, the above SMTP mailing doesn't work.

Also, the customer has a 3rd Party Medical App which sends/receives mail within the Medical system app (so has its own mail client showing Inbox/Sent etc - I believe POP). A 2nd Mailbox was agreed to for the Medical App mail.....

In an effort to get POP & SMTP working, I disabled Security Defaults and I thought enabled SMTP Auth, but this appears to have broken the Customer's initial Authenticator Challenge with Outlook..... Also didn't manage to get the SMTP to work (was using App Password, which with Basic gone sounds a dead option).....

The above is a very typical Small Business set of needs (certainly in NZ, but likely worldwide I'd expect), hence I'm trying to get this and other customers over to 365 & away from ISPs so they get the benefit of Outlook across devices, Calendars, Addressbooks etc, but still need to have those Support Apps - UPS, Backup software & embedded Mail Clients working.....

Hence the request for a simple doco that covers this general scenario, with the intended MS dropping of Basic all combined & working for a NEW Tenant (who will be Security Defaults enabled) & also showing turning on 2FA & configuring - as they will be related topics, but a single doc (that's current i.e. written on what's to be & moving forward, not written based on what has been able to work - which is where I've been stuck referring to recent stuff that's about previous how to - not now how to) that covers this scenario for the many out there trying to do this for their customers.....

Appreciate the response though ViliusS , so I'm hoping someone in the Exchange Team can think this out & whip up a doco that covers it, as this is holding up moving more customers from their ISP mail (traditional) to 365 for us, as we don't want to mix in SMTP2Go type solutions for the Alerts/Backup msgs & have another Domain at an ISP to handle the integrated Mail Client within their essential apps, otherwise what's the point of going 365 for them - that would be the question pushed back & unanswerable from a cost perspective..... 

Cheers

G