Programmatically prevent Windows screensaver from starting

Question

Is there a recommended way to prevent the Windows screensaver from starting? The closest thing I\'ve found is this article, but what I would really like to do is just tell

Answer 1

From MSDN:

Windows does not start the screen saver if any of the following conditions exist:

• The active application is not a Windows-based application.
• A CBT window is present.
• The active application receives the WM_SYSCOMMAND message with the wParam parameter set to the SC_SCREENSAVE value, but it does not pass the message to the DefWindowProc function.

There's a caveat though:

Windows Vista and later: If password protection is enabled by policy, the screen saver is started regardless of what an application does with the SC_SCREENSAVE notification.

That seems to apply even if you use the SetThreadExecutionState with ES_CONTINUOUS.

So, if it weren't for the caveat, your choices would be:

1. SetThreadExecutionState with ES_CONTINUOUS (as described in other answers).
2. Put up a computer-based training window (which requires hooks).
3. Don't let the WM_SYSCOMMAND with SC_SCREENSAVE be passed onto DefWindowProc. (Assuming you care only when your application is the active application.)
4. Install a dongle that simulates mouse jiggle.

The last option is nice in that it works even with the password protection policy.