Configuring Outlook Express to Authenticate to a Remote Mail Server

By Weldon Whipple <>

SMTP (Simple Mail Transfer Protocol) Authentication lets you send e-mail from your e-mail client through a remote mail server to other e-mail addresses on the Internet.

If your ISP's e-mail server supports SMTP authentication (SMTP AUTH), here is how to configure your Outlook Express e-mail client to send your user name and password to the mail server. (These steps apply to version 6; other versions might differ slightly.)

  1. While in Outlook Express, select Tools > Accounts > Mail
  2. Select existing account and click "Properties". (If this is a new account, click Add > Mail.)
  3. On the "General" tab, specify values as appropriate.
  4. On the "Servers" tab:
    1. Specify information about incoming servers (for POP/IMAP, etc.)
    2. Specify server for "Outgoing mail (SMTP):" (Example:
    3. Under "Outgoing Mail Server," check the "My server requires authentication" checkbox.
    4. Click the "Settings..." button.
    5. Check the "Log on using" button, then enter your e-mail account name and password. (If your outgoing e-mail user name and password are the same as your incoming ones, you might be able to check the button that reads "Use same settings as my incoming mail server.")
    6. Check the "Remember password" button.
    7. Do not check the "Log on using Secure Password Authentication" checkbox, even if your outgoing mail server is configured to use STARTTLS. (See below.)
  5. If your server is configured to use STARTTLS, click the "Advanced" tab, then (Under "Outgoing mail (SMTP)") click the checkbox next to "This server requires a secure connection (SSL)"
  6. Click "OK" until you have exited the configuration dialogs.

If you don't send mail through your ISP's mail server--and if your ISP blocks port 25 except to its server--you might still be able to reach your outgoing SMTP server through a different port. (AOL blocks port 25, but allows 5190; I have heard of some SMTP servers that accept SMTP connections on port 5190! Also try port 587 (the mail submission port.) Try the following:

  1. Click the "Advanced" tab.
  2. Enter "5190" or "587" as the outgoing server port number.

Click "OK", "Apply", etc., until you are back to the Outlook Express main window. (You might want to exit OE and restart.)

Now you can relay e-mail through your e-mail server, based on supplying the correct user name and password.