Installing a TestFlight app on iOS iPhone Simulator - Registration Failed

If you need test your Release application you can run your on a release build go to ->Product->Scheme -> Edit scheme-> in Run change debug to Release in this you can check your release build in simulator

The app you are trying to install is an app compiled for arm architecture, which is different from the simulator (the simulator is not an emulator). The simulator only runs x86 apps compiled for it. You will need to contact the developer of the application to send you the x86 binaries, and add them directly to the application directory of the iOS simulator. The directory (on Xcode 4.5 beta 4) is /Applications/Xcode45-DP4.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator5.1.sdk/Applications. Note that the simulator's sdk version has to match the version of iOS you are trying to use the simulator with.