black final image when using compositing nodes

Hey everyone,
I’m trying to use Blender’s internal node compositor for an animation I’m working on, and when I hit ‘render’ it’ll go through the entire render, then finally when it’s finished the render buffer will go black. I have ‘Do Composite’ selected in the render settings, and ‘Use Nodes’ in the Node Editor activated, yet even the simplest of setups (i.e. a ‘Render Layers’ node feeding into a ‘Composite’ node via ‘Image’) causes this to happen. I’ve tested using compositing nodes on simpler scenes, and they work fine, but on my more complex scene it’s not working for me. Any clues as to why this is?

Could you post a sample blend file of your problem? (or is this only in your animation file and comp nodes work in other files?)

do you have vector blur in there?
if so, you need to enable "Vec " in the render layer settings.
Also, make sure your render layers are setup correctly.