Lock Screen Timeout Not Saving? Here's the Real Fix

Quick answer for advanced users

Run powercfg -list and powercfg -attributes to check for overrides, then check Group Policy under Computer Configuration\Administrative Templates\Control Panel\Personalization for "Screen saver timeout" or "Enable screen saver". If none, delete HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\InactivityTimeoutSecs and ScreenSaverIsSecure keys.

Why the setting won't stick

This has been a headache since Windows 10 Pro with the 1903 update, and it carried over to Windows 11 22H2. The culprit is almost always a power plan setting that's overriding your lock screen timeout. But it can also be a group policy from your IT department or even a dumb registry key left over from a third-party utility. You change it in Settings, it looks fine, then next time you unlock the PC it's back to 1 minute or 5 minutes. Don't bother with the Settings UI again — it's just a mirror. You need to go after the real control.

Step-by-step fix

Check your active power plan. Open Command Prompt as admin. Run powercfg -getactivescheme. It'll show the GUID. Write it down.
List all display timeout settings. Run powercfg -q GUID (replace GUID with yours). Look for SUB_VIDEO and SUB_SLEEP. Find VIDEOIDLE and VIDEODIM. If they're set to anything other than 0 (never), they'll override your lock screen timeout.
Set them to 0. Run powercfg -change -standby-timeout-ac 0 and powercfg -change -standby-timeout-dc 0. Also powercfg -change -monitor-timeout-ac 0 and powercfg -change -monitor-timeout-dc 0. This kills any power timeout that could override the lock screen.
Kill group policy overrides. Press Win+R, type gpedit.msc (Pro/Enterprise only). Go to Computer Configuration > Administrative Templates > Control Panel > Personalization. Find "Screen saver timeout" and set it to Not Configured. Same for "Enable screen saver".
Check registry for leftover junk. Open Regedit. Go to HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System. If you see InactivityTimeoutSecs or ScreenSaverIsSecure, delete them. Reboot.

Alternative fixes if the main one fails

If steps 1-5 don't fix it, try this:

Create a new power plan. In Control Panel > Power Options, click "Create a power plan" and pick Balanced. Set it as active. Then go back to the plan settings and change the lock screen timeout there. I've seen corrupt plans that just refuse to save.
Run the System File Checker. Open cmd as admin and run sfc /scannow. It can fix corrupted system files that mess with setting persistence. Takes 10 minutes.
Disable fast startup. In Control Panel > Power Options > Choose what the power buttons do > Change settings that are currently unavailable. Uncheck "Turn on fast startup". That feature has a nasty habit of caching old settings.

Prevention tip

Once you get the timeout to stick, lock it down by running this in an elevated PowerShell: powercfg -setacvalueindex SCHEME_CURRENT SUB_VIDEO VIDEOIDLE 0 and powercfg -setactive SCHEME_CURRENT. That writes the value directly to the active scheme without relying on the Settings app. Also, don't install any "tweaker" apps that change power settings — they're usually buggy and undo your work. Keep Windows updated, but skip feature updates for 3 months until the big bugs are patched.