I'm solving many systems of two equations by varying the initial parameters. I'm running FindRoot in a NestWhileList where the NestWhileList counter allows me to alter parameter values and feed in current solutions as the start point for the next system. My NestWhileList index runs up to 5000 and when I run it I get 8 or 9 error messages, so far of two kinds. They are
line search decreased step size to within tolerance...
General::stop: "Further output of FindRoot will be suppressed during this calculation."
Now I'd like to know for which NestWhileList index was the error generated.
This is a minimal working example similar to the code that I am running. In this example, I start with a start point sol and look for solutions. Then the counter increases, the new start point sol is the previous solution + the increment from the previous start point: add. The list d is some vector of parameter values.
d = {0, 0, 0, 0, 0};
sol = {0, 0};
add = {0.5, 0.5}
counter = 5;
data = NestWhileList[{#[[1]] + 1,{x, y} = {x, y} /.FindRoot[{x + y == #[[1]]*#[[1]], x- y == d[[#[[1]]]]}, {x, #[[2]][[1]] + #[[3]] [[1]]}, {y, \#[[2]][[2]] + #[[3]][[2]]}],{x - #[[2]][[1]], y - #[[2]][[2]]}} &,{1, sol, add},Not[2 < #[[2]][[2]] < #[[2]][[1]] < 3] &, 2, counter]
Of course, this simple example gives no errors. I'd love to be able to figure out which index is (or which all indices are) generating errors so I can go look it up individually in detail and see if the error is because a solution doesn't exist or it does exist but my output is not that solution or maybe everything is fine and I can ignore the messages. I'd love it if you can tell me how this NestWhileList error tracker can be extended to a Table setting.

Check[]? $\endgroup$Check. Now I am looking atCheckandCheckAbortto see if I can implement it withNestWhileListin a productive way. $\endgroup$