Intermittent errors emailing using Office 365 as an SMTP server
Some sites are experiencing intermittent errors when emailing using Office 365 as an SMTP server. This is because Microsoft are removing older ‘basic’ authentication methods from Microsoft 365. Originally from December 2022 but they keep giving reprieves.
At any rate, customers using Microsoft 365 as an SMTP server for their emailing, website(s) or multi-function devices (printer, scanner, etc) will begin to receive ‘401 (Unauthorized)’ or similar error messages from time to time.
Since your site is using Office 365 anyway, what you need to do is start using Jiwa’s Microsoft Graph REST API plugin for emailing. This includes the latest features and security of Office 365 emailing and is available for Jiwa version 7.2.1 onwards.
See here for details: