You may reply to a bulletin board message in the following way:
Open the relevant bulletin board, select the message that you wish to reply to and press the 
button. The view will switch to Compose View and OfficeTalk will automatically set up
the subject, prefixed with 'Re:', and will indent the original text, positioning the caret ready for you to type in your reply. The bulletin board containing the message will be set up as the
recipient of the message.
Enter your reply into the message window and press Ctrl+S to send the message.
Your message will appear indented under the original message in the bulletin board.