Hi,
There is already a topic with this subject but my circumstances seem to be different. I have one Office365 mailbox with my main e-mail address, I also have an alternative "alias" for this e-mail address in the form of a distribution group, in case this is relevant. Outlook 2013 works fine, no problems at all, receiving e-mails via IMAP works fine too. I cannot send anything via SMTP though. I used the following settings:
Server name: smtp.office365.com
Port: 587
Encryption method: TLS
I am trying to use my main e-mail address so I'm guessing it has nothing to do with the fact I also have this distribution group. I have no idea what I am missing here and it happens on two different e-mail clients: Thunderbird/Windows and K9Mail/Android. Please help.