Kenneth Fisher explains his debugging technique:
Almost everything is made up of smaller pieces. When you are running across a problem, (well, after you check the stupid things) start breaking up what you are doing into smaller pieces. I’m going to give a simplified version of an actual example of something I did recently. No code examples (sorry), just discussion, and only most of the tests so you can get the idea.
The problem
I’m running a job that runs a bat file that uses SQLCMD to run a stored procedure that references a linked server. I’m getting a double hop error.
There’s some good advice in here. My slight modification to this is that if you have strong priors as to the probability distribution of the cause, hit the top one or two items (in terms of likelihood of being the cause of failure) first, and if that doesn’t fix it, then go from the beginning. This assumes a reasonable probability distribution, which typically means that you have experienced the problem (or something much like it) before.