LeoMoon SessionGuard is a free portable app that prevents your machine from sleeping or restarting without changing any settings.

It works by registering a ShutdownBlockReasonCreate() reason and objecting to WM_QUERYENDSESSION messages. It resides in the systray awaiting deployment and includes limited settings like emulating mouse moves, starting with Windows, and hotkey selection.

An app such as LeoMoon SessionGuard is useful when your employer forces screen-saver/screen timeout to lock your computer as part of their internal policies. Or just for personal use when watching movies or other activities requiring a stop to activate the screen-saver. LeoMoon SessionGuard is also capable of stopping Windows automatic restarts.

LeoMoon SessionGuard Features:

Does not modify any Windows settings

Stops screen-saver/screen-timeout to lock your computer using SetThreadExecutionState

Stops system restart using ShutdownBlockReasonCreate

Can emulate mouse movement every x seconds

Use [Ctrl]+[Win]+['1'] to enable/disable

Similar:

How-to Manage Startup Apps in Windows 10 & 11

How to Disable the Windows 10 & 11 Task Scheduler Privacy and Automatic Maintenance Related Tasks