To rename some of the images inside the Media Manager, follow these steps:
1. Go to Content - Media Manager
2. Find the Image to rename and hover the mouse over it and click on the pencil icon to rename the image:
3. Rename it without spaces and all lower case letter then click "OK":
IMPORTANT NOTE: If an image is renamed while it is being used by the Brand Images, Homepage Layout Settings, Banner Ads or Web Pages is will appear as broken. This happens because the file path or file URL of the image in the code is now incorrect, since the image no longer uses that name.
Below are some examples -