Error code 0x800CCC0F is generated when sending mail from Microsoft Outlook . This error is generated because the mail client ( Outlook ) is unable to contact the MailEnable server. The most likely reason is because a firewall is preventing connectivity between the client and the server.
Not sure why you created another post answer this question. Quoting your answer here for other who come looking for it: " Click on your email account >> More Settings >> Outlook Server. Now, click on the checkbox next to the option “My outgoing server (SMTP) requires authentication”. At last, you need to click on the “Log on to incoming server before sending mail” option to fix this Microsoft Outlook email error code and message."