OutLook Express/Can’t Display Stationery

I recently started using OutLook Express for my email. I have had no problems with it, except for it not displaying the stationery in sent messages. They show when I write them, but the recipient always recieves the text plain, and the background stationery as an attachment. I have sent messages to myself through three different email clients, and it does it with all of them, including hotmail. Even the default stationerys with OE are received as attachments. How can I fix this? Feel free to respond to my above email, as well as here. Thank you.