Point to "Tools" in the menu bar at the top of the screen. In the drop down box select "Preferences."
If you use Outlook Express but are not sure which version, you can easily check. In your Outlook account click on "Help." Select the drop down option, "About Microsoft Outlook Express." There you will see your version number.
If you turned off the confirmation message when you were sending email, the "Don't show confirmation window if there are no errors" box will be checked. If you have had a change of heart, you can click to uncheck it.