In February 2021 Microsoft announced that basic authentication would be deprecated some time in the second half of 2021) but extended the deadline due to popular demand. Just a couple of days ago Microsoft announced that the final deadline for the Basic Authentication is October 1.
But why are we posting about this here? Well, the Enterprise Alert E-Mail Module does support Basic Authentication for on-prem and Online Exchange and the authentication method is most likely still used by some.
We strongly recommend you to switch your Online exchange integration from Basic Authentication to more secure authentication method like OAuth.
Setting up OAuth for office 365 – Derdack (zendesk.com)
If you do struggle or have further questions please feel free to reach out to our Derdack support team under support@derdack.com.