Basic auth

[ElyesZaag]

Our problem today is that we have an IIS 6.0 relay smtp with a login and password with the O365 SMTP. (basic authentication)

And as a result of the new Microsoft authentication, my SMTP relay server may no longer work.

Can you confirm that my relay server may no longer work?
If so, do you know of any Windows software that can do modern authentication to replace my relay SMTP server?

[#2]

Hello,
I can guess your Windows SMTP Server is using the Option 1 described here

https://learn.microsoft.com/en-us/exchange/mail-flow-best-practices/how-to-set-up-a-multifunction-de...

If that is the case, that is SMTP Auth and is not going to be disabled just now

See here for latest news https://techcommunity.microsoft.com/t5/exchange-team-blog/basic-authentication-deprecation-in-exchan...

[#3]

@AndresGorzelany 

SMTP is still good to go after Basic Auth disable in Oct:

Basic Authentication and Exchange Online – September 2021 Update - Microsoft Tech Community

[#4]

Exactly...