PC 连接 to windows phone 7 设备 程序运行到app.launch() 报错,该如何解决

PC 连接 to windows phone 7 设备 程序运行到app.launch() 报错
The app can be launched to Emulator but to real device failed,When I debug to method RemoteApplication.Launch() lead error as below:

Microsoft.SmartDevice.Connectivity.SmartDeviceException was unhandled
  Message=0x80040202
  Source=Microsoft.SmartDevice.Connectivity
  ErrorCode=-2147220990
  StackTrace:
  at Microsoft.SmartDevice.Connectivity.RemoteApplication.Launch()
  at DeveiceAutomationTest_Desktop.DeveiceControl.ApplicationManager.InstallApplicationAndLaunch(Device deviceObj, Guid applicationGuid, String iconFileName, String xapFileName) in E:\work\WP7AutomationTest_Demo\DeveiceAutomationTest_Desktop\DeveiceControl\ApplicationManager.cs:line 29
  at DeveiceAutomationTest_Desktop.Program.Main(String[] args) in E:\work\WP7AutomationTest_Demo\DeveiceAutomationTest_Desktop\Program.cs:line 38
  at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
  at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
  at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
  at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
  at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean ignoreSyncCtx)
  at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
  at System.Threading.ThreadHelper.ThreadStart()
  InnerException: 

I refer to http://justinangel.net/WindowsPhone7EmulatorAutomation.

The screen is unlocked and I checked Name of phoneSdk.GetDevices() that the device name is correct.I use HTC 7 MOZART T8698
Thanks!

------解决方案--------------------
清理,重新编译
------解决方案--------------------
The 'Hello World!' app can be launched to device or not?