SetThreadExecutionState is not working when called from windows service

Question

I want prevent system from going to sleep/hibernate from a windows service. I am calling SetThreadExecutionState function to do that. But it seems to have no effec

Answer 1

Calling SetThreadExecutionState without ES_CONTINUOUS simply resets the idle timer; to keep the display or system in the working state, the thread must call SetThreadExecutionState periodically.

(source)

You need to call this function every now and then. It's not a fire-and-forget.