I had same error code for me, task was running day before correctly. After changing schedule, it stopped working and started giving error code "2147942405".

I tried running the "Start the program" exe path manually, it worked. Then I tried to run schedule manually, same issue, error code "2147942405".

So i decided to "recreate" task from scratch, deleted existing task, created new one, same setting, same user profile etc..., with different task "Name", then I run it manually, and it worked.

Afterwards, the next occurence of schedule was executed correctly.