title: “MSVCP100.dll is either not designed to run on Windows or it contains an error”
body: <p>I built an application in C++ using Visual Studio 2010 Express. When I tried to run it on a certain computer today I got this error:</p>
  
  <blockquote>
    <p><strong>MyApplication.exe - Bad Image</strong></p>
    
    <p>C:\Path to My Application\MSVCP100.dll is either not designed to run on Windows or it contains an error. Try installing the program again using the original installation media or contact your system administrator or the software vendor for support.</p>
  </blockquote>
  
  <p>The DLL mentioned is one of the Visual C++ Redistributable DLLs. My application’s installer used to launch Microsoft’s installer for those DLLs but I recently tweaked it just to install msvcp100.dll and msvcr100.dll alongside my application. The new way worked fine on a handful of other computers, though I can’t rule out the possibility that that was only because the DLLs had already been installed at system level on those other computers.</p>
  
  <p>What is causing this sudden DLL mismatch?</p>