title: How do I fix the Visual Studio compile error, "mismatch between processor architecture"?
body: <p>I'm new to project configuration in Visual Studio 2010, but I've done some <a href="http://visualstudiohacks.com/articles/visual-studio-net-platform-target-explained/" rel="noreferrer">research</a> and still can't quite figure this issue out. I have a Visual Studio solution with a C++ DLL referencing the C# DLL. The C# DLL references a few other DLLs, some within my project and some external. When I try to compile the C++ DLL, I get this warning:</p>
  
  <blockquote>
    <p>warning MSB3270: There was a mismatch between the processor architecture of the project being build "MSIL" and the processor architecture of the reference "[internal C# dll]", "x86".</p>
  </blockquote>
  
  <p>It tells me to go to Configuration Manager to align my architectures. The C# DLL is set up with platform target x86. If I try to change this to something else, like Any CPU, it complains because one of the external DLLs <em>it</em> depends on has platform target x86.</p>
  
  <p>When I look at Configuration Manager it shows the Platform for my C# DLL as x86 and for my C++ project as Win32. This seems like the right setup; surely I don't want the project for my C++ project to have platform set to x64, which is the only other option presented.</p>
  
  <p>What am I doing wrong here?</p>