Attempting to load C# solution in Monodevelop, getting error: 'Unknown Solution Type'

When I try to load a solution this is the error messagebox I'm getting: http://i.stack.imgur.com/cKUwP.开发者_StackOverflow中文版png

It was originally a Visual Studio 2010 project in Windows which I'm trying to port to different platforms (i.e. iOS, Android, OSX, Linux).

It's not an error loading the solution, it's an error loading the projects inside the solution. It seems that those particular projects are project types or subtypes that are not supported by MonoDevelop.

In particular, it looks the the XNA Content project type and the XNA subtype (or flavor) of the C# project type. Note that VS wouldn't be able to open these project either if you didn't have XNA installed.