Problems when sending emails via SMTP with accounts

This week Microsoft made some changes on their mail servers, which disabled OAuth login for the SMTP protocol on their accounts. This means those using free MS accounts, such as,, and similar stopped being able to send emails from eM Client, the messages either got stuck in Outbox or you received this error:

[SMTP] MailClient.Accounts.AuthenticationAbortedException: Authentication aborted.

We have reported the problem to Microsoft and also created a workaround for eM Client which you can use until Microsoft fixes this issue on their side. Please follow the link below to our Knowledgebase:

eM Client: Cannot send emails for accounts - Authentication aborted