'glCreateShader' was not declared in this scope?

What does glGetString(GL_VERSION) return?

CreateShader is not in GLUT but OpenGL 2.0. If your "includes to glut" are not including gl.h for some reason or your GL version is less than 2.0, the headers will not declare it.

I'd also check your gl.h to see if CreateShader is actually declared there.

Edit: This OpenGL header version thing seems to be a general problem in Windows. Most people suggest using GLEW or another extension loader library to get around it.

You need to either use an OpenGL loading library to load OpenGL functions, or manually load the functions yourself. You can't just use gl.h and expect to get everything.