You can replace an old media file with an edited or new version.
Note
If the media file is currently used in one or more spots, it's automatically replaced there as well. This may affect the layout of those spots.
To replace media, perform the following steps:
Go to Content > Media management.
In the Selectable media pane, select the media file and click Replace spot.
In the Upload manager, select the file to replace the existing media and upload it.