Have you created a window with support for multisampling?
I always use glew to check the OpenGL extensions.
In order to be able to initialize GLEW and multisampling, we need to first create a simple OpenGL window, then initialize GLEW, then check for Multisampling and finally try to create a window which supports multisampling( If your implementation supports multisampling ). how many samples have you used for WGL_SAMPLES_ARB?
you need to use larger values such as 4, 8 or 16 to see better and better results.
Enabling multisampling using glEnable(GL_MULTISAMPLE ) without creating a window with support for multisampling doesn’t enable multisampling.