Cannot use offsets when Pixel Unpack Buffer Object is disabled?

OpenGL Development
#1

So I’m trying to learn about FBOs from this tutorial: http://www.opengl-tutorial.org/intermediate-tutorials/tutorial-14-render-to-texture/

This line causes me some problems:
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, 800, 600, 0, GL_RGB, GL_UNSIGNED_BYTE, 0);

The exception says “Cannot use offsets when Pixel Unpack Buffer Object is disabled”, so I tried glEnable(GL_PIXEL_UNPACK_BUFFER)
and then it still gave me the exception. Any help?