Hi @lburr - thanks for your excellent explanation.  Unfortunately, I'm having the same issue...maybe years later, Intuit finally has a patch?

My scheduled backups stopped working on April 14th, followed by daily 12kb TMP files - my last successful scheduled backup was April 13th.  It will backup to the attached USB hard drive without issue if run manually, but scheduled does not work.  I did go into the Task Scheduler and followed the steps you used with success, although I had to select Windows 10 as that's what I'm running my QB Premier 2016 on.  Unfortunately, I am still getting TMP files.  All I see in Task Scheduler when I look at the Last Run Result column is (0x2).  

Any other thoughts or ideas?  Did your changes permanently fix your issue?

Thanks...

Jason