Summary. After checking that Outlook is setup and configured properly, by pressing the “Test Account Settings” button during email account setup, and observing that all tests show a green check mark indicating Outlook is configured properly. It may be that E-mail sent to one’s own account are received. However, attempting to send e-mail to someone outside your email host results in an error such as “550 not local host, not a gateway.” In this example, is provided. The local host name will be the domain name of the person who you are e-mailing.

Solution. It may be necessary to setup SMTP authentication for proper sending. Follow these steps for Outlook 2003:

  1. From the Outlook Tools Menu, choose E-Mail Accounts
  2. View or change existing e-mail accounts, next
  3. Click/highlight the e-mail account in question, then click the Change button
  4. Click the More Settings button
  5. On the Outgoing Server tab, place a checkmark in the box for “My outgoing server (SMTP) requires authentication.” Click OK.
  6. You should be back at the E-mail Accounts setup panel for the account you are working with. Click Next.
  7. You should be back at the list of e-mail accounts. Click the Finish button.