Bat files failing silently in Task Scheduler. Steps to fix both character encoding and exit codes

I run a task that generates and posts music at a set time every week.One day, the "Last Run Result" in Task Scheduler was 0, ...
Ars Technica

Server 2008R2 - Task Scheduler - Last Run Result (0x7)

Action is "Start a Program" The program is a batch file The batch file spools up some Java (Pentaho Data Integration), does some work, then exits Nothing in any of ...