Universal CDN allows you to customize HTTP error pages. You can set a different error page for several response status codes.
To set up an error page to an HTTP error response status code, follow the steps outlined below:
1. Log in to the Universal CDN Control Panel at my.ucdn.com.
2. Navigate to the My Zones tab located in the top left corner.
3. Click on the cogwheel icon 
next to your CDN Zone.
4. Navigate to the Error pages handling tab.
5. To enable a custom page for a specific error code, tick the box in front of the HTTP status code and enter the full URL of your custom error page in the field below.
6. Click on the Save Changes button.
You can find detailed information on HTTP status codes here!
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