Please use this forum if you have questions about using the XML price feed, and we will try to help.
If you are developing a new application, use the relevant sample file links on the http://xml.dgcsc.org/instructions.htm
page to test until you get it right, then you won't use up your credit during development.
If you are having trouble getting the file using https try getting it with http (some platforms have trouble with our secure certificate)
If you are still having trouble getting the file, use the browser on the server to try to get the file, perhaps the server/firewall is blocking the call.