When I attach a file to my email, why does it sometimes go in the body instead of the header?

Usually this has to do with the format of the email. When you send new email messages through Outlook, by default they are set to be HTML emails. However, some mail programs use Rich Text or Plain Text messaging. If you are replying to a Rich Text email, you’ll notice that the attachment goes in the body of the email. If you are replying to an HTML or Plain Text email, it will go in the Attachment line.

To see what kind of message it is:

In Outlook 2003 you can look on the Send toolbar. At the far right end, there is a drop-down box that will say HTML, Rich Text, or Plain Text.

In Outlook 2007 & 2010 look on the Options tab in the Format group.