When you create a WCF web service in Visual Studio, by default the service is hosted in IIS Express and only accepts connections at http://localhost/. Apps that target Windows Phone OS 7.1 can connect to the development computer as localhost because the Windows Phone 7.1 emulator uses the network connection of the development computer. The Windows Phone 8 Emulator, however, configures itself as a separate device on the network. As a result, an app running on the Windows Phone 8 Emulator can’t connect to the development computer as localhost.
All the relevant Details about this can be found at the following link
But the Problem is that this solutions too gives problems and the emulator won't consume a web service, just yet, but fortunately, one of our brilliant interns here at MIC Lahore, Saad Mahmood, has come up with a solution that can help resolve the isssues.
When you intend to consume a web service, you generally come across the following exception,
for a resolution,
Everything goes fine here but the problem in windows phone 8 is this that consuming WCF is not that much charm in WP8
you do all steps but still you fail, here is the solution to the problem
When ever you use your ip address you consume WCF first register it .
CMD provides native command that can be used for registering the URL for cashing.
You can Follow the steps in the Blog Post by Saad Mahmood on the following Link