Maybe you want to try Glenn Barnas' Task Scheduler UDFs. The ScheduleTask() UDF is designed for simple one-off task scheduling. Secondly, you're complaining about problems with JT.EXE and not the ScheduleTask UDF, thus you'll need to contact Microsoft to figure out why certain things don't work, in general JT.EXE is buggy and does not support the full range of the Task Scheduler options, also the JT.EXE documentation is not entirely correct either. The ScheduleTask UDF works as written.
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