If Outlook is receiving email but you are getting an error when you send, it could be that your port is being blocked.

  1. Open up Outlook
  2. Go to Tools < email accounts or Account settings
  3. Double click on your email account or select and edit
  4. Select More settings on the Internet E-Mail Setting Screen
  5. Select the Advanced Tab
  6. Change your Outgoing server (SMTP) Port from 25 (this can be blocked) to 587
See Also
Update a login email address
Emailing Groups