I have been moving individual email tasks to authenticate with Graph and everything is working perfectly.
Yesterday, I moved a task that uses the Send As privileged to send as a different user. This has been working fine with the prior SMTP authentication. With Graph, I get this error:
Unable to send email as [correct email address]. Access denied. Will try default mailbox.
Then, it seems to send as expected. I’m note sure if it is falling back to SMTP authentication. The history is:
Charley