Please explain in a lot more detail what your issue is. Exact version of AE you're currently using, what version you were using, what hardware you're running, etc.
And, most importantly, we need to know what you mean about CUDA working vs. not working. Are you talking about the ray-traced renderer, the GPU effects, or something else?
I didnt work using raytraced rendering yet. The real "problem" happen when I open the software, and, when I play the timeline, it use the basic mercury rendering. In the Premiere software, I need to pre render the timeline to see the effects in real time. Today I'm using the premiere CC 2017 and this things are happening, but, the same file in the previous version of the software, worked very well. In After Effects, the warning about CUDA is the same.
I'm working with Nvidia Geforce GT 420.
I asked to the adobe support about my problem and, one of the suggestion was update the video driver. It doesn't make sense for me because another softwares like illustrator 2017 has worked very well. So, I entered the nvidia site and I downloaded the driver. Ok... Now the CUDA resources works well.
thanks for sharing what worked