What does "Service exited with abnormal code: 1" mean?
When you run a program (such as your script that deletes user profiles) - it will leave behind an exit status code when done executing.

The exit status code is 0 when everything has gone according to plan. Anything other than 0 is an "abnormal code", usually indicating some kind of error or warning.

The exit status code 1 is just a "generic error" - it could mean anything. You'll have to look into the script you have to see which exit status codes it uses, and what the causes of them are.