Between top-down, bottom-up and divide-and-conquer what is the appropriate approach to debug sofware issues

I had difficulties running the application due to software issues. As I investigated different possibilities, I found that there were dependency packages that were required in order the application to run.

Once the package were properly installed, then the application ran. I would like to know which approach did I used to accomplish this?

Bottom-Up, Top-Down, or Divide-and-Conquer?