I have a wall switch that control outside lighting (there is another switch that controls the same light) with two red and two black along with a ground. The instructions with the digital timer does not indicate how to address two black and two red wires... Can you help?

Sounds like you presently have a couple of 3-way switches. Also sounds like you are in the load switch of the two 3-ways. Is the timer switch a 3-way, does the timer switch require a neutral. You may or may not be able to use it and may or not be able to use it at the location you are trying to put it.