SMTP client submission

Microsoft Plans to Disable SMTP Authenticated Submissions in Exchange Online

by Tony Redmond

Microsoft is doing its level best to remove SMTP basic authentication from Exchange Online as quickly as possible. Basic auth for SMTP connections will disappear gradually as time goes by. Tenants can make accounts more secure by removing SMTP authentication from accounts, something that Microsoft will do in the future when these connections are not used. An exception exists (for now) for SMTP client submissions, but these might also be affected in the future.