MonoGame is a multi-platform framework to write games using the .NET Framework relying on the Mono Project. But if you try to create a Desktop game on Windows 7 using it, you will probably run into a missing file: xinput1_3.dll. The reason for that is that it uses SharpDX, which is a wrapper for DirectX. Going to the SharpDX download page you will find the runtime requirements for it:
- .NET Framework installed
- For desktop, the DirectX June 2010 Redistributable Runtime
- For Windows 8 Metro, the DirectX11.1 is already part of the OS.
So, as I told you on the first line, you only have to install the DirectX June 2010 Redistributable Runtime and you will be good to go!