EmailDLL Online Manual
Returns: Success or Error Status
This methods deletes any non-standard header lines that you previously added with the Email.AddOtherHeader() method. There are many optional header lines that indicate various information to the email client. A listing of the accepted headers is beyond the scope of this help file.
While it is certainly safer to call this method, it is not really necessary to do so unless you are sending more than one email message with a single Email class, and you also are setting non-standard header lines. Unless, of course, you have other reasons for doing so.