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POWhy can't get the main window handle for a started process?
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copied!<p>I have a situation where I'm starting a process in my code in order to set up an IPC channel. The process I'm starting is an MFC application with no CLR support. The application from which I am starting this process is a C# module in a WPF application (thought I don't think that that is consequential to my problem). This works with a version of the application that does support CLR, and it works on every computer except the deployment target, a touch screen computer with Windows 7. But for some reason, when I try it with this exact scenario, the Process object never resolves a main window handle (<code>Process.MainWindowHandle</code>). Is there another (perhaps even pinvoke) method of doing this? Is this a security thing? I'm the one staring the process. The process's main window handle does exist. I don't see what could be wrong.</p> <p>If it helps, here is my code. </p> <pre><code> _applicationProcess = new Process(); _applicationProcess.StartInfo.FileName = _strProcessPath; _applicationProcess.StartInfo.Arguments = _strProcessArguments; _applicationProcess.Start(); long nTicks = Environment.TickCount; if (_applicationProcess.WaitForInputIdle(1 /*minute(s)*/ * 60000)) { try { do { // Don't let total processing take more than 1 minute(s). if (Environment.TickCount > nTicks + 1 /*minute(s)*/ * 60000) throw new ApplicationException("MFCApplication.Startup failed! The main window handle is zero!"); _applicationProcess.Refresh(); } while (_applicationProcess.MainWindowHandle.ToInt32() == 0); _applicationHandle = new IntPtr(_applicationProcess.MainWindowHandle.ToInt32()); } catch (Exception ex) { //Do some stuff... throw; } } else { // Do exception handling. } </code></pre> <p>The <code>ApplicationException</code> is hit after a minute of trying to get a main window handle other than zero.</p>

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