Windows 10 Dynamic Lock Not Working: Making Your PC Lock When Your Phone Walks Away

You set up Dynamic Lock so your PC would lock itself whenever you step away with your phone. Yet you come back from lunch and the desktop is still wide open. When Windows 10 Dynamic Lock not working leaves the screen unlocked, the feature you trusted for privacy is quietly doing nothing.

Dynamic Lock uses Bluetooth to watch the signal strength of a paired phone. When the signal drops below a certain level for about 30 seconds, Windows assumes you have left and locks the PC.

That means it depends on three things: Bluetooth staying on, the phone being properly paired, and the PC being idle for a short time after you leave. If any of these is missing, the lock never triggers.

It is also not instant. Even when it works correctly, there slot is a delay of up to a minute, so it should be seen as a backup to pressing Windows + L, not a replacement.

Why This Happens

Dynamic Lock fails for these reasons:

• Bluetooth is off on the PC or the phone.
• The phone was paired as an audio device or not paired at all.
• “Allow Windows to automatically lock your device when you’re away” is turned off.
• Power-saving settings turn off the Bluetooth adapter.

Some phones put Bluetooth to sleep when the screen is off, which makes the PC think you are still nearby or confuses the signal reading.

Start With These Basic Checks

Confirm the setup.

1. Open Settings > Devices > Bluetooth & other devices and make sure Bluetooth is on and your phone shows as Paired.
2. If the phone is missing, select “Add Bluetooth or other device” and pair it again.
3. Open Settings > Accounts > Sign-in options and scroll to Dynamic lock.
4. Tick “Allow Windows to automatically lock your device when you’re away.”
5. Check that the message underneath names your phone.

Test by walking well out of range, at least 10 metres away or into another room, and wait a full minute.

Going a Step Further

Keep the Bluetooth link stable.

1. Open Device Manager, expand Bluetooth, and open the adapter’s Properties.
2. On the Power Management tab, clear the option that lets Windows turn off the device to save power.
3. Update the Bluetooth driver from the PC maker’s support page.
4. On the phone, disable battery optimisation for Bluetooth-related apps if the setting is available.
5. Remove the phone from the PC’s Bluetooth list and pair it again cleanly.

If the PC lock still fails, set a short screen timeout with “Require sign-in” so it locks anyway.

A Word of Caution

Never rely on Dynamic Lock alone in an office or public place. Press Windows + L every time you leave the desk, since the delay gives others a short window to use your session.

Final Thoughts

Dynamic Lock needs a paired phone, active Bluetooth, and the setting turned on. Check all three, stop power saving from cutting the adapter, and keep using Windows + L as your main habit.