How to set up Dynamic Lock on Windows 10 Creators Update
Let Windows 10 automatically lock the PC
One of the new features in Windows 10 ‘Creators Update’, working on build 15031 or newer, is the Dynamic Lock. This is a security feature you can find in Settings → Accounts → Sign-in options. Turning the feature on would allow Windows 10 to automatically lock the PC if a Bluetooth-paired phone is out of proximity range for more than 30 seconds.
Here is now you can set up Dynamic Lock in Windows 10*
Pair a phone using Bluetooth.
Turn on Bluetooth on both the phone and the PC. Go to Settings → Devices → Bluetooth. Pair both devices.
Enable Dynamic Lock. Open Settings → Accounts.
Go to Sign-in options.
Check the ‘Allow Windows to detect when you are away‘
Now your PC should lock as soon as it detects that you with the Bluetooth-paired phone walk out of proximity range. You must log-in again to unlock the PC.
*Currently, Dynamic Lock is still in development and available only for Insiders in the Fast Ring. Keep in mind that there could be some issues with the new feature in the Preview builds. But everything should be polished by April, in time for the official Creators Update for Windows 10.