how to integrate a thrid party saas application to use office 365 SMTP

Question

Hi,

i am looking for a solutions, where we have a third party application as SaaS service. we like that application to utilize the office 365 SMTP server for outgoing message.
when we are testing it, it is throwing an error with invalid username and password i am able to login with those credentials via outlook OWA.

we are in a hybrid setup for office 365.

Thanks in advance.

pavan.

Answer 1

Probably because SMTP Basic Auth is disabled in the tenant:
https://learn.microsoft.com/en-us/exchange/clients-and-mobile-in-exchange-online/deprecation-of-basic-authentication-exchange-online

Note you can reenable it, but only until Oct of this year:
https://learn.microsoft.com/en-us/exchange/clients-and-mobile-in-exchange-online/authenticated-client-smtp-submission

If that is the case, then you will need to find another solution soon using Modern Auth or not sending through 365