Hello, 

I am a client of Bell Sympatico in Canada.  Just purchased Office 365 and trying to configure Outlook.  I also installed Windows 8.1

Using the required POP3  information and required SMTP configuration, Outlook receives emails but no emails will get out.  Using the same configuration on Outlook 2010 on another computer everything works fine.  Bell Sympatico technicians could not figure out the problem even when they took control of my PC.  

Configuration :  outgoing mail server smtphm.sympatico.ca

Checked box regarding "My outgoing server (SMTP)requires authentication

Server port numbers  Incoming POP3 995

Checked box "this server requires an encrypted connection (SSL)

Outgoing server (SMTP) 25

Use the follwing type of encrypted connection : Auto

Hello,

From the description, the issue seems related to client. On one side, I recommend you contact Bell Sympatico vendor, on the other side, I recommend you post your issue to office 365 forum.

http://community.office365.com/en-us/forums/default.aspx