Delete files from My Media
The easiest way to delete a video, audio, or image across all Media Libraries is to delete it from the My Media view.
First, navigate to My Media by clicking the "My Media" link on the top-right, under your name.
Then, click Media options (and then "Settings" from the dropdown menu) for the file you want to globally delete. You can also use the "Find" feature to search in real-time.
At the upper-left of the Media options view, click the "Remove from Media Library" link.
You'll be asked to verify your choice. Check the "Delete this media from all Media Libraries" checkbox to delete all copies of the file. Click "Remove" if you're sure.
Finally, you'll see a popup. Click "OK" if you're really sure.