Compositor renders white (I'm a compositor noob and I need help!)

So prior to finishing up everything else, this did work, but the glare was put ontop of everything. Ok so I went through and did the rest of the animation but now my entire compositor renders white. Ive given up at this point, It is setup for the sun (the white emission ball in this case) to give a glare, but I need the glare to only happen behind earth, especially not being shown THROUGH it like it has been. Here’s my node setup, I’m lost, I am a noob to the compositor, someone please help me

https://drive.google.com/file/d/0B-Pb4UUmmaWtYnQxenpQQjYxWUE/view

I suppose we have to use guesswork to figure out what your scene looks like since you have failed to supply a simple demo blend file, something everyone should be supplying at the very minimum for ALL support questions.

Why would you use “Screen” for the final composite?