You may already be aware that Microsoft had announced the deprecation of Basic Authentication on March 1, 2026 due to potential security risks. This meant that any applications or services relying on Basic Authentication for sending email through Microsoft 365 or Exchange Online will stop functioning as expected after that date.

Microsoft have now adjusted the deadline to December 2026.

Updated Exchange Online SMTP AUTH Basic Authentication Deprecation Timeline | Microsoft Community Hub

  • Now to December 2026: SMTP AUTH Basic Authentication behavior remains unchanged.
  • End of December 2026: SMTP AUTH Basic Authentication will be disabled by default for existing tenants. Administrators will still be able to enable it if needed.
  • New tenants created after December 2026: SMTP AUTH Basic Authentication will be unavailable by default. OAuth will be the supported authentication method.
  • Second half of 2027: Microsoft will announce the final removal date for SMTP AUTH Basic Authentication.

What this means to you

This will affect all sites using Office 365 or Exchange Online with B4B Payments and Remittances, iPOS, Collect and CSB.

PA's email delivery system relies on Basic Authentication via SMTP. In response to the notification from Microsoft, PA have developed the SMTP to Graph Gateway application that uses OATH2 for modern, secure authentication. The key benefits of this are:-

  • Enhanced security and compliance
  • Improvements on reliability
  • Future proof support beyond 2026

If you are affected by this change from Microsoft, please log a FreshDesk ticket - https://support.professionaladvantage.co.uk/. We will then send you a link to download the SMTP for Graph Gateway for your IT to install.

And, for further information from Infor refer to this post - Deprecation of Basic Authentication support for SunSystems 6.1 – 6.3 after December 2026 - Infor Global Community