This could be happening for any number of reasons. I need to know more about the scene in order to figure out what's happening though.
1. Do you have a camera set up or are you just rendering the viewport view?
2. Do you have lights set up or are you just using the default lighting? If you had lights in the scene but then deleted them, then you will have no light in your scene at all. You will then have to either manually reset the default lighting or just insert a light.
3. If you're using a daylight system, have you set the proper exposure control in the environment settings?
4. Are you rendering with Mental Ray or the Scanline renderer? Or are you using Vray?
5. Have you applied materials to the objects in your scene? If so, what are they.
I would normally ask that you post your file here, but since you're using 2012, I won't be able to open your file here on 2011.
If all else fails, and you can't get the render to work, open a new instance of Studio Max and Merge your scene objects into the new file. Or export your scene objects to .obj format and then import them into a new file.