Delete Sent Facebook Message
Step 1: Sign in to your Facebook account.
Step 2: Click the "Messages" switch in the menu on the left to open the Messages page.
Action 3: Click the conversation that contains the sent messages you want to remove. Facebook shows conversation threads in day order with one of the most current below the page.
Step 4: Click the "Actions" switch on top of the conversation screen.
Tip 5: Select "Delete Messages" from the pull-down menu.
Action 6: Click to enable the check box next to each sent message that you intend to delete.
Action 7: Click the "Delete Selected" switch and then click "Delete Messages" in the confirmation pop-up window. Facebook eliminates the chosen messages.
Pointer: To remove a whole conversation, including all gotten as well as sent messages, click the "Delete All" choice after opening up the "Delete Messages" display.