[Iron_Cross]

Well first you need to go through the steps that it said, so that it can show you the source code. But what it's saying is that you're trying to use an object that hasn't been instantiated.

e.g.

static void Main(string[] args)
{
    SomeObject smObj;
    smObj.DoSomething();
}

Since you never instantiated smObj

Hope this helps.