In addition to the comments of The Dark, NEVER include module files (*.cpp)
Include <string> for "cerr << Horrors << endl".
I think he got the KillProcess code largely from
here. You might want to include that function in your code instead, and modify it so it accepts a filename instead of a process ID.
In C++ try to use C++ strings. When you really need to convert to C strings, you can do so with the c_str() function.
Lastly, As The Dark mentions, the ofstream constructor has default modes of ios::out and ios::trunc, you can change those to whatever you like.