Windows 10 Windows 10 Task Scheduler Skips Schedule execution of task for days, then starts running it again

[IlikeToSki]

I' have a simple script file that runs every 2 hours, daily. It has executed flawlessly for over a year, since my upgrade to 10. Recently, (late Jan), it now doesn't always run the task. It will skip the task for a day or two, then start executing it again. There are no error messages, nothing in the log file. It just doesn't run on its scheduled time. It will run manually from within scheduler, but not according to the schedule. This computer is unattended, so nothing additional has been installed.

I even reformatted hard drive and reinstalled windows 10, a very basic system, very limited other programs installed, (office 2010 is).

I'm wondering if a recent windows update may be the culprit. Weird how it runs according to schedule, then doesn't.

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