You need the Global Messaging Admin permission to delete a global message. You would delete a broadcast message after it has been sent if you neglected to select an end date for the message and you want to remove it from user Dashboards. You can also delete a global message before it has been sent if circumstances change and the message is no longer valid or relevant.
1. Click Admin in the Navigation Toolbar, and click the Global Messaging link in the menu.
2. In the Global Messages screen, locate the message you want to delete under the Alert, Information, or Warning heading.
Global messages are listed alphabetically by the subject of the message.
3. Click the global message record to display a screen whose name reflects the subject of the message, and click Delete in the toolbar.
4. In the Delete Global Message prompt, click Yes.