Today I worked with a customer that had an interesting problem They have kiosks that auto-login and they don't want those machines to lock or pop a screen saver.
We thought we turned it off with a GPO, but it was still auto-locking after period of time.
The cause was a gem hidden in the settings menu under Accounts and Sign-in options.
"If you’ve been away, when should Windows require you to sign in again?”
Toggling that switch fixed it.
Monitoring that change in ProcMon points to this registry value:
Path: HKEY_CURRENT_USER\Control Panel\DesktopName: DelayLockIntervalType: REG_DWORDValue:0