When you forward or reply to an email, the original message will be appended to the email. To customize the introductory text citation that will appear before that original message, do the following:
Click the Settings link, located in the upper right corner of the webmail window.
Click Compose Email, located in the left pane.
In the Replying & Formatting Citations section, you can make adjustments to the citations that are included in email you reply to and forward. Select an option from the When I reply to an email, include drop-down menu. To see examples, click the See Examples link.
If you selected User-Defined, you can enter customized start and end text, in the User-defined start text and User-defined end text boxes.