What to use when SMTP AUTH for Exchange Online is Retired
Back in April 2024, the Microsoft Exchange team announced they intended to remove Basic Authentication (SMTP AUTH) in preference for customers using the more secure OAuth model.
This will occur in September 2025 at which point Microsoft will start rejecting the logins with the following error:
550 5.7.30 Basic authentication is not supported for Client Submission.
Microsoft published a few options in their announcement but the core solution for most clients sending less than 1,000 emails a month is going to be the Azure Communication Service. This allows you to relay emails through Azure with easy and quick settings for your Multi Function Printers and Scanners and other services.
Pricing is outlined on the ‘Messaging Tab’ here , but as of May 2025, it’s £0.00019/Email sent and £0.00009/MB transferred. So 500 emails at 1MB each is £0.14.
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For Administrators looking to set this up, here is my quick fire guide:
1) Create an Azure Communication Service
2) Create an Azure Communication Email Service (yes both are needed)
3) Add your Custom Domain to the Email Service
4) Link that to the Communication Service
5) Create and Register a App Registration
Create a Secret and save the value
6) Add the Application to the Azure Communication Service (Not the Resource Group or Subscription, must be direct! on the Communication Service itself. Also not the email service)
Then create an SMTP Username
7) Send an email:
-Server: smtp.azurecomm.net
-Port: Port 587 (recommended) or port 25
-TLS / StartTLS: Enabled-Username: [The SMTP username you created in step 6]
-Password: [The Secret ‘Value’ you created in Step 5]
And you’re DONE!
On a quick run this setup took 8 min’s to do the whole run through.
If you’re looking for help with setting up your Multi-function Printers with Scan to Email, or any other product that requires email relay, Tetrabyte Remote I.T. Support is a fixed cost, full coverage IT Support package ready to help your team with any IT issue. Just give us a call on 0330 900 1066 and let us start helping you today.
