By default in Microsoft Exchange Server 2003, the sending of out-of-office reply messages to the Internet is disabled. Many administrators do not allow out-of-office reply messages to be sent outside the Exchange organization to prevent unauthorized people from learning when users are out of the office.

To enable out-of-office reply messages to the Internet, follow these steps:
1. Start Exchange System Manager.
2. Double-click Global Settings, and then click Internet Message Formats.
3. In the details pane, right-click a domain name, and then click Properties. (Note By default, “*” is the SMTP domain.)
4. In the Default Properties dialog box, click Advanced, and then click to select the Allow out of office responses check box.
This allows out-of-office reply messages to be sent under this SMTP policy.