POP3 e-mail clients cannot send messages to remote domains (828048)

SYMPTOMS

When you configure your user accounts to connect to your Microsoft Windows Small Business Server 2003 server by using a POP3 connection, your users may experience both the following symptoms:

When your users send e-mail messages to other users who are in the internal domain, the messages are delivered successfully.
When your users send e-mail messages to other users who are in an external domain, your users receive a delivery status notification (DSN) message that indicates that Microsoft Exchange Server 2003 cannot relay the message to the destination domain.

CAUSE

This problem occurs if your user accounts that you configured to use the POP3 connection are located outside the external interface for your Windows Small Business Server 2003 computer. Exchange Server 2003 is configured to prevent messages from being relayed from users who are outside the external interface of Windows Small Business Server 2003. Exchange Server 2003 is configured this way to help prevent Exchange Server 2003 from being used to deliver unsolicited commercial e-mail (UCE). UCE is also known as spam.

RESOLUTION

To resolve this problem, configure Microsoft Office Outlook 2003 on the client computers to send authentication to the outgoing SMTP server. To do this, follow these steps:

On the client computer, start Office Outlook 2003.
On the Tools menu, click E-mail Accounts.
Leave the View or change existing e-mail accounts option selected, and then click Next.
Click the account that connects to the Windows Small Business Server 2003 server by using a POP3 connection, and then click Change.
Click More Settings, click the Outgoing Server tab, and then click to select the My outgoing server (SMTP) requires authentication check box.
Leave the Use same settings as my incoming mail server option selected, click OK, click Next, and then click Finish.

MORE INFORMATION

For additional information about support for Windows Small Business Server 2003, visit the following Microsoft Web site:

http://www.microsoft.com/windowsserver2003/sbs/support/default.mspx