How to build Master server for free?

Hi!
I’m trying to build a master server. I have followed this tutorial Create Your Own Unity 3D Master Server! - YouTube

I have also read the doc on unity which states that it’s a Visual Studio 2008 solution.
http://docs.unity3d.com/Documentation/Components/net-MasterServerBuild.html

I did try downloading the 2012 express and when i did try to open it. Visual Studio informed me it was “incompatible”.

Can any one explain what I should do?

I did try Visual C++ 2010 Express and it did work!