c++ Forms

I don't understand how to call another form from a button click event in one form.  In c# I could write something like:

Form2 theOtherForm = new Form2();

theOtherForm.ShowDialog();

When I try to do something like this in C++, it gives me error C3673.

I read about the error here:
http://msdn.microsoft.com/en-us/library/ms173670(VS.80).aspx

I didn't understand it though.

Can someone explain to me what I'm doing wrong.

HIJACK

So i had a telephone interview for a c++ role yesterday. I hate c++ so am never too passionate about them, and tend to expect the interviewer to be a complete retard who sucks oo cock but can't actually program to save his life. Needless to say, this was no exception. He asked me what the difference between an object and a class is in c++. I was like "what?". I thought a class was just c++'s keyword for an object. Unless he was talking about o./.obj compilers, but that seems a bit of a strange question.