I’m assuming you want something similar to the attached image.
- The mirror object, environment, lamp and camera go on layer 1.
- The monkey goes on layer 2.
- Go to Scene panel (F10)
- Open Render layers tab.
- Make sure both layers are selected in the Scene layer section (green arrow)
- Uncheck the Monkey layer (second layer) in the Render layer section (yellow arrow)
- Press the Render button (F12). Press it for Glory!
Why this works:
The scene layers in the Render Layer panel are equivalent to the layer controls present in the 3D window. They determine what is to be rendered. Render layers are used primarily when working with nodes. The render layer is the composite of your scene layers and render passes.
What we’re doing here is using the scene layers to provide the render pipeline with everything on layer 1 and 2 (step 5).
However, we’ve also told the pipeline to ignore layer 2 when building the render layer (step 6). Since the monkey is on layer 2, it gets ignored. But since its shadow and reflection are present on the mirror plane layer 1, they get included.
If this gets you the effect you want, can you please put [solved] in the title.
Hope this helps. Blend file also included for fun and great justice.