The "Error: source not supported." image in Inform players is a generic error message that populates when the player cannot function properly.
There could be a number of different issues causing this; however, the one seen most often is that the file is being blocked from playback. Check that the http://informmeidap-a.akamaihd.net domain is unblocked, whitelisted, or have the configuration changed to do so.
Contact your Inform manager or PartnerSupport@inform.com for more information.