cj06,
Show us the whole line that calls SU. I suspect you may have omitted the %comspec% which is needed for redirect '<' to work.
I don't (won't) use SU because of the security risk but read somewhere the using enviro vars is the way to go. Personally I'd use Task Scheduler.
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Give a man a fish and he will be back for more. Slap him with a fish and he will go away forever.
