C-Sharp Window Phone Apps is not working.

When we tried to connect MindcrackerWindowPhone App from my Windows Phone Mobile. I got the following error. there was no endpoint listening at http://66.29.197.117/windowsphoneMindcrackerServices/ArticleService.svc that could accept the message. This is often causd by an incorrect address or SOAP action. set InnerException, if Preset for more details.