Office365 Authentication Issue 5.7.139

Currently using version 8.5.9 with PHP 7.4.33, and we’ve run into an issue with the SMTP details declining.

The error we’re getting is

5.7.139 Authentication unsuccessful, the request did not meet the criteria to be authenticated successfully. Contact your administrator. [ 2023-06-29T23:09:40.243Z 08DB78ADA0BE6197]

We’ve disabled MFA and enabled SMTP on the accounts, we can log in to the OWA using the credentials, so we know they’re valid. Has anyone come across this and know what I need to check in Azure to make sure we can log in?

Yeah typically the first thought here is MFA - but otherwise it’s like the error says - you have some criteria that is not being met by the request, i.e. it’s on the Azure side. You might tripe check that MFA is actually disabled for the account AND that it’s not required to use SSO or something.