Thank you for the update. Since you have already completed the previously suggested steps, I would avoid making any further registry changes for now.
Because the same behavior is occurring on two Windows 11 laptops and one Windows 10 PC, could you clarify the following?
- Does the screen saver start when you select Preview?
- Which screen saver is selected: Blank, Photos, or a third-party screen saver?
- Do the three computers share any common hardware or software, such as a wireless mouse receiver, docking station, controller, remote-access software, or synchronization utility?
As a focused test, please select Blank, set Wait to 1 minute, and disconnect non-essential USB or Bluetooth devices. Then leave the computer at the desktop without touching the keyboard or mouse.
If the screen saver still does not start, try a clean boot on just one of the affected computers. This can help determine whether a background service or startup application is continually registering activity and preventing the idle timer from being reached. Microsoft’s clean boot instructions are available here: How to perform a clean boot in Windows.
Please let me know whether Preview works and whether the screen saver starts during the clean boot test. Those two results will help distinguish a screen saver configuration problem from interference caused by software or connected hardware. Thank you so much for your understanding.
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