Render Doesn't Work!

Hey, I’m new to blender and I’m having some issues with rendering my file. I began to put the animation together but I need to figure out why my the render comes up with a grey screen. I’m sure it’s something simple.

I tried to upload the file, but is doesnt seem to be working. Any ideas would be great!

Ensure you have not disabled renderability of objects in the outliner window
If you are not using the video editor or compositor ensure there is nothing loaded that would render in place of your scene. if so remove them or disable in the Render / Post Processing panel
Check you have lighting
Check objects are on enabled layers

Or just upload blend file to and tell us the download link