I am practicing Microsoft net framework training kit. The problem is that the solution/projects were made by Visual Studio 2008. I use Visual Studio 2012.

The projects are unavailable.
![image](https://i.stack.imgur.com/bTcUv.png)

I want to modify the solution file and project files. Just worry about messing up them.

Another snapshot:
![snapshot](https://i.stack.imgur.com/68GCc.png)

How to modify them by editor then I can load them with visual studio 2012?