It would be helpful if you gave us a more detailed explanation of the problem. For now, let's ignore the cards you're using and focus on what you have implemented rather than what the names of the pieces are.
You're creating a voltage at one point and trying to read it at the second. Are you starting this by using a straight-through or are you doing your conversion? If you're doing conversion, take a step-back and use the straight-through. With this, do you see the input and output matching? Until you can get this wired correctly, it's a waste to do anything more. How are you measuring the voltage values? Are you using a DMM to measure values at the pins or are you using an indicator of some form?
Next, simply telling us analog to digital is practically useless. We would need to see your code to see how you're trying to implement this. We'd also need to know the input range and the desired resolution of the digital output. Without those, we really can only offer general theory.
