Delete Sent Facebook Message
Action 1: Sign in to your Facebook account.
Step 2: Click the "Messages" button in the menu on the left to open the Messages page.
Action 3: Click the conversation that contains the sent messages you wish to remove. Facebook shows conversation strings in day order with one of the most recent at the end of the page.
Step 4: Click the "Actions" switch on top of the conversation display.
Step 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 erase.
Action 7: Click the "Delete Selected" button and then click "Delete Messages" in the confirmation pop-up window. Facebook eliminates the chosen messages.
Suggestion: To delete an entire conversation, consisting of all gotten and also sent messages, click the "Delete All" choice after opening the "Delete Messages" display.