My wife's computer with Windows 10 won't honor the screen timeout settings in Settings/Power and Sleep. Specifically, what happens is that the screen blanks for less than a second and then the screen comes back on. (And yes, the system won't sleep, either.)
If I explicitly tell the computer to sleep, it goes to sleep as expected.
I've checked the usual settings issues, and I've come to the tentative conclusion that one of the apps she's running is vetoing the sleep request.
Any ideas on how to figure out which app is causing this behavior?