How to use dynamic lock to automatically lock your windows 10 pc

How to use dynamic lock to automatically lock your windows 10 pc

This page provides recommendations on what to do if your computer frequently freezes or completely halts. To determine if your computer is frozen, press the Num Lock button on the keyboard and watch if the Num Lock LED turns off and on.

If you can get the light to turn off and on, press Ctrl + Alt + Del and End Task the frozen program, otherwise, proceed through each of the following sections in order.

Software related issue

A computer locking up or freezing is often is caused by software related issues. If you are encountering lockups when the computer is opening a particular program, make sure you have all the latest updates for all running programs. You can find the latest updates for your software through the software developer or publisher.

If the computer has any malware, virus, or other malicious software, it can also cause many problems. How do I remove a virus and malware from my computer?

Too many programs open

Each program or window you open on your computer takes some of the computer’s resources to keep it running. If you have too many programs open at one time, your computer may be low on resources, and as a result, is freezing. Try only running one program at a time to make sure your freezing is not being caused by multiple programs running at the same time.

Driver related issue

A computer lock up can also be caused by outdated or corrupted drivers. For example, if there is an issue that exists with your video adapter drivers, your computer could lock up while playing a game.

First, make sure no errors exist in the Windows Device Manager by opening the Device Manager and verifying that no “Other Devices” are listed. You also want to check the device list to see if any of them have a yellow exclamation mark or red X next to them.

Next, make sure you have the latest drivers for all major devices in your computer (video, sound, modem, and network). For a list of driver-related help pages, see our drivers index.

Operating system related issue

Make sure your operating system has all of the latest updates installed on it.

Heat-related issue

If the computer processor is getting too hot, it can cause the computer to freeze. If you have heard any abnormal noises coming from your computer recently, such as a high squealing, it could indicate a failing fan.

Verify the power supply fan is working by examining the back of the computer and seeing if the fan is moving and moving smoothly. For the other fans in the computer, you have a few options. You can either open the computer and physically inspect them or, if the RPM is mentioned in BIOS setup make sure it doesn’t report any errors.

Laptop users can prop their laptop on a book to help air reach the bottom of the laptop and determine if it has a heat-related issues.

Users may also be able to determine how hot their computer is by onboard thermal sensors. If your computer comes equipped with these sensors, make sure your CPU is not running too hot.

Hardware issue

Some of the steps below require you to open your computer. While working inside of a computer, be aware of ESD.

A hardware malfunction or misconfiguration can cause a computer to lock up. If you have recently added any new hardware into the computer, temporarily remove it to make sure it is not causing your issue.

Before attempting to remove any hardware, make sure the computer has no conflicts in Device Manager.

If you have not recently installed any new hardware, the next best solution is to remove certain components one by one. For example, you may remove your modem, network card, sound card, or any other expansion cards because they are not needed for the computer to operate. Run the computer without these cards to see if they’re causing the issue. Also, try unplugging any peripheral (plugged in) devices one at a time to see if they’re causing your issues.

A serious issue with Windows

If, after trying the above recommendations and the computer continues to lock up frequently, Windows is corrupt. Try running through the basic troubleshooting steps for your version of Windows on our basic troubleshooting page. If these additional steps do not resolve your issue, we suggest you back up all of your valuable information, and then erase and reinstall Windows.

Hardware failure

If your computer turns off abnormally during or after the installation of your operating system, hardware components inside your computer may be malfunctioning. If so, the failing hardware is likely the RAM, CPU, motherboard, or power supply (in that order).

If you access the same parts from another computer known to be working, try swapping the parts to isolate the faulty hardware. Otherwise, you need to have the computer serviced.

Using GPO or Registry, you can configure Windows to auto lock itself after inactivity or a user not using the computer for some time. Here’s how.

You can lock a Windows PC in a number of ways. Though not hard, locking Windows 10 is still a manual action. If you want to, you can configure Windows 10 to lock automatically after inactivity. You can specify the inactivity time like ten minutes, fifteen minutes, etc. If you find yourself frequently moving away from your computer then auto-locking Windows is quite useful and secure too.

In this quick guide, let me show the procedure to auto lock Windows after inactivity.

Steps to Auto Lock Windows 10 After Inactivity

The easiest way to make Windows 10 lock itself is to use the Group Policy editor. In the editor, you change a single policy and you are done. Do keep in mind that this method only works on pro and enterprise versions of Windows 10. If you are using Windows 10 home version then follow the second method. i.e, registry method.

Enable Windows Auto Lock After Inactivity via GPO

  1. Open the Start menu.
  2. Search and open “gpedit.msc“.
    How to use dynamic lock to automatically lock your windows 10 pc
  3. In the GPO Editor, go to the following folder.
    Computer Configuration → Windows Settings → Security Settings → Local Policies → Security Options
    How to use dynamic lock to automatically lock your windows 10 pc
  4. Double-click on the “Interactive Logon: Machine inactivity limit” policy.
    How to use dynamic lock to automatically lock your windows 10 pc
  5. Type number of seconds after which you want Windows 10 to lock itself automatically. Choose the number of seconds between 1 and 599940.
    How to use dynamic lock to automatically lock your windows 10 pc
  6. Click on the “Apply” button.
  7. Click “Ok“.
  8. Close Group Policy Editor.
  9. Reboot Windows.
    How to use dynamic lock to automatically lock your windows 10 pc

After restarting, the policy will be applied. From now on, the computer will lock itself after the specified inactivity time.

To disable auto lock, just set the seconds value to 0 or empty in step 5 and save the changes.

Registry Method to Automatically Lock Windows 10 After Inactivity

If you are using Windows 10 home version, then you need to use the registry editor to automatically lock the computer. All you have to do is create a single value. Though editing registry for this specific purpose is nothing hard, I’d recommend you to backup the registry. The backup allows you to restore the registry if anything bad happens.

1. First, open the start menu, search for Registry Editor and press the enter button to open it.

How to use dynamic lock to automatically lock your windows 10 pc

2. In the registry editor, copy the below path, paste it in the editor’s address bar and press Enter . You will be instantly taken to the folder where you need to add the new value.

How to use dynamic lock to automatically lock your windows 10 pc

3. We now need to create a new DWORD value. So, make sure the System folder is selected in the left panel. Next, right-click on the right panel and select “New -> DWORD (32-bit) Value” option.

How to use dynamic lock to automatically lock your windows 10 pc

4. Name the new DWORD value as “InactivityTimeoutSecs” and press Enter to confirm the name.

How to use dynamic lock to automatically lock your windows 10 pc

5. After creating the DWORD value, double-click on the value. In the Edit Value window, select the “Decimal” radio option and enter the number of seconds in the blank field. Make sure that the number is seconds are between 1 and 599940. In my case, I’m entering 600 for 10 minutes. Click on the “Ok” button to save the changes.

How to use dynamic lock to automatically lock your windows 10 pc

6. This is how it looks like in the registry editor after setting up the value.

How to use dynamic lock to automatically lock your windows 10 pc

7. To apply the changes we just made, reboot your system.

How to use dynamic lock to automatically lock your windows 10 pc

After rebooting, your computer will automatically lock after inactivity. If you want to disable the automatic lock feature, all you have to do is enter 0 in step 5 or delete the InactivityTimeoutSecs DWORD value.

That is all. It is that simple to configure Windows 10 to automatically lock itself after inactivity.

Chris Hoffman is Editor-in-Chief of How-To Geek. He’s written about technology for over a decade and was a PCWorld columnist for two years. Chris has written for The New York Times, been interviewed as a technology expert on TV stations like Miami’s NBC 6, and had his work covered by news outlets like the BBC. Since 2011, Chris has written over 2,000 articles that have been read nearly one billion times—and that’s just here at How-To Geek. Read more.

How to use dynamic lock to automatically lock your windows 10 pc

Windows 10’s Creators Update adds Dynamic Lock, which tries to automatically lock your PC when you step away. Dynamic Lock uses Bluetooth to check the signal strength of your smartphone. If the signal drops to a certain level, Windows assumes you’ve walked away with your smartphone and locks your PC.

Where Windows Hello allows you to automatically unlock your PC with a , Dynamic Lock allows you to automatically lock your PC. This feature is reportedly known as “Windows Goodbye” internally at Microsoft. Once you’ve paired your phone with your PC using Bluetooth and enabled Dynamic Lock, all you have to do to lock your PC is walk away. Here’s how to get it set up.

Pair Your Smartphone With Your PC

Before you can enable Dynamic Lock, you’ll need to pair your smartphone with your PC using Bluetooth. Dynamic Lock can’t connect to your phone and check its Bluetooth signal strength unless you do.

Start by putting your smartphone into pairing mode. On an iPhone or Android, you can do this by heading to Settings > Bluetooth. While at this screen, if Bluetooth is on, your phone will be discoverable.

How to use dynamic lock to automatically lock your windows 10 pc

Next, start the pairing process on your Windows 10 PC. Head to Settings > Devices > Bluetooth & other devices, click “Add Bluetooth or other device”, and then click “Bluetooth” to pair a Bluetooth device with your PC. You’ll see your phone in the list if it’s discoverable, although it may take a few moments to appear. Click your phone and confirm that the PIN matches on both your phone and PC when prompted. You’ll be informed the pairing process is complete.

How to use dynamic lock to automatically lock your windows 10 pc

Enable Dynamic Lock

To enable Dynamic Lock, head to Settings > Accounts > Sign-in options, scroll down to the “Dynamic Lock” section, and check the “Allow Windows to detect when you’re away and automatically lock the device” option.

If you can’t check the box, you probably haven’t paired your smartphone with your Windows 10 PC using Bluetooth yet.

If you don’t see this option here at all, your Windows 10 PC probably hasn’t upgraded to the Creators Update yet.

How to use dynamic lock to automatically lock your windows 10 pc

Windows 10 doesn’t provide any other options for configuring dynamic lock here. There’s no way to choose which Bluetooth device Dynamic Lock relies on, although it should use your smartphone. Microsoft’s official documentation says that Dynamic Lock requires a paired smartphone, although the Settings app refers vaguely to “devices that are paired to your PC”.

Dynamic Lock may also work with other devices like smartwatches, but don’t count on it. Microsoft doesn’t want Dynamic Lock to use Bluetooth devices you may leave near your PC at all times, like mice and keyboards.

Use Dynamic Lock

Take your phone with you, step away from your computer, and it will automatically lock about a minute after you step out of range. Note that different devices have different signal strengths, so the exact distance you need to travel before your PC locks will vary.

Your PC will also lock itself a minute after you turn off Bluetooth on your phone. That’s because Windows can no longer see your phone is nearby. Fortunately, waiting for a minute also helps prevent your PC from locking when you don’t want it to just because Bluetooth looses its signal for a few moments.

How to use dynamic lock to automatically lock your windows 10 pc

When you come back to your PC, you’ll have to sign into your PC manually—either by entering a password, providing a PIN, or using a Windows Hello sign-in method. Dynamic Lock doesn’t automatically unlock your PC when the Bluetooth device comes back within range.

How to use dynamic lock to automatically lock your windows 10 pc

When you walk away from your PC, you should always lock it. But sometimes you forget. Here is how to make Windows 10 automatically lock when you want it to.

When you walk away from your computer, you want to make sure to lock it so other people can’t access your machine and its data. You can, of course, manually lock your Windows 10 PC down by hitting Windows Key + L or Ctrl + Alt + Del. But sometimes you forget. The cool thing is you can make Windows 10 to lock automatically after a set time of inactivity. Here is a look at a few ways you can set this up.

Lock Windows 10 Automatically Using Your Screen Saver

This is probably the simplest method and an old trick. Open Start and type: change screen saver and click on the “Best Match” result.

How to use dynamic lock to automatically lock your windows 10 pc

Next, the Screen Saver Setting windows will come up. Set your screen saver to something from the dropdown list. Personally, I just use the “Blank” option. But the important thing to do is make sure to check the “On resume, display logon screen” box and set the “Wait” time to however many minutes you want and click OK.

How to use dynamic lock to automatically lock your windows 10 pc

That’s all there is to it. After the period of inactivity that you set up, your screen saver will come up and require you to enter your PIN or password to unlock it.

Make Windows 10 Lock Automatically Using SecPol

Now, time to get geekier. If you’re running the Pro version of Windows, you can use the Local Security Policy feature. To launch it, hit Windows Key + R and type: secpol.msc and click OK or hit Enter.

How to use dynamic lock to automatically lock your windows 10 pc

Open Local Policies > Security Options and then scroll down and double-click “Interactive Logon: Machine inactivity limit” from the list.

How to use dynamic lock to automatically lock your windows 10 pc

Enter the amount of time you want Windows 10 to shut down after no activity on the machine. When the Limit Properties window opens, you can type in an inactivity limit between one to 599940 seconds. Just keep in mind that the max is 166 hours, and you won’t want the number of seconds too low as it would get annoying to have your PC lock all the time.

When you’re finished, you need to sign out of your session or restart your PC for the changes to take place.

How to use dynamic lock to automatically lock your windows 10 pc

When it comes to figuring out the number of seconds to use, here it’s good to use some time unit conversions with your favorite search engine. For example, 10 minutes would be 600 seconds.

How to use dynamic lock to automatically lock your windows 10 pc

Enable Windows 10 Auto Lock Using the Registry

If you are running Windows 10 Home, you don’t have access to the Local Security Policy tool. However, you can do the same thing by hacking the Registry. But this is a method only experienced users can try. If you’re on Windows 10 Home, you might just want to use the Screen Saver trick.

To get started, hit Windows Key + R and type: regedit and click OK or hit Enter to launch the Registry.

How to use dynamic lock to automatically lock your windows 10 pc

Then head to the following path:

Now create a new 32-bit DWORD Value called InactivityTimeoutSecs and give it a value between 0 or 599940 – again, that is the number of seconds of inactivity you want to pass before locking your system.

How to use dynamic lock to automatically lock your windows 10 pc

Then sign out of your session or restart your PC for the settings to go into effect. If you want to change the time, just go back into the InactivityTimeoutSecs key and change it.

Whether you go the simple route or get geekier by digging into your system, this is a good thing to have set up if you walk away from your machine and forget to lock it down. You will need to change the time values depending on the situation you’re in, but having the auto-lock backup will provide extra peace of mind.

Forget to lock your PC? Dynamic Lock does it for you — here’s how.

The Windows 10 Creators Update arrives April 11, and when it reaches your PC, you’ll have a new way to lock it when you get up to grab a cup of coffee, chat with co-workers, or otherwise leave your computer unattended.

That’s because a new feature called Dynamic Lock can automatically lock your PC when your Bluetooth phone goes out of range.

We wouldn’t say it’s one of the very best new features in Windows 10 — here’s a list of our top 10 favorites — but it’s a pretty neat addition. Here’s how it works.

Step 1: Pair your phone

Before you enable Dynamic Lock, you must first pair your phone with your PC. You can skip down to step 2 if that’s already done.

  • On your PC, go to Settings > Devices > Bluetooth & other devices.
  • Turn on Bluetooth with the toggle switch there. (Turn on your phone’s Bluetooth as well).
  • Next, tap the “+” button for Add Bluetooth or other device.
  • In the pop-up Add a device window, tap Bluetooth, then choose your device from the list that appears.
  • Prompts should appear on both your PC and phone. Accept them to pair.

In my case, my iPhone wasn’t listed after the laptop scanned for Bluetooth devices (it saw only my Apple TV). Updating my laptop’s Bluetooth driver, however, fixed the problem.

To update your PC’s Bluetooth driver:

  • Open the Device Manager (press the Start button and type in “Device Manager”), then click to expand the Bluetooth line.
  • Next, right-click on the first Bluetooth item listed (mine says Bluetooth USB Module), tap Update driver and then choose Search automatically for updated driver software.

Step 2: Activate Dynamic Lock

With your PC and phone paired:

  • Go to Settings >Accounts and then tap Sign-in options in the left panel.
  • Scroll way down to the Dynamic Lock section and check the box for Allow Windows to detect when you’re away and automatically lock the device.
  • That’s it!

Dynamic Lock in action

Just know that Dynamic Lock isn’t a foolproof security mechanism for these three reasons (at least as of today):

  • Your PC stays unlocked until you walk out of Bluetooth range
  • Your PC still stays unlocked for 30 seconds after that
  • If someone hops onto your PC while it’s unlocked, Dynamic Lock won’t engage at all

When I walked to the other side of my house, put my phone down and returned to my PC, I didn’t see the lock screen even by the time I sat down — but just before I started muttering nasty things about Bluetooth and betas, the PC suddenly locked.

If you regularly lock your PC when you leave your desk, then perhaps Dynamic Lock can be useful as a safety net, kicking in to lock your PC should you forget, perhaps when you run out of your office after receiving an email about free pizza in the conference room.

Bluetooth issues

Dynamic Lock also forces you to rely on the connection mysteries of Bluetooth. You probably don’t need me to tell you that Bluetooth connections can be far from reliable. Perhaps it’s just a function of the beta or particular to my phone and laptop, but the connection dropped between my iPhone and my Windows laptop after Dynamic Lock locked the laptop. (This didn’t happen for my colleague Sean Hollister, who used a Surface Book and Android phone.)

Each time I entered my password to unlock my laptop, the connection between my iPhone and PC dropped. The laptop kept reporting that the two were paired, but my iPhone showed them unconnected. Making matters worse, I couldn’t simply tap to reconnect but had to remove the devices and go through the pairing process all over again.

No unlock

I was also a little disappointed to learn there’s no Dynamic Unlock part of the equation. The Dynamic Lock feature only locks your PC when you and your Bluetooth phone wander out of range. It doesn’t magically unlock it when you get back to your desk. For that, you’ll need a face-recognizing IR webcam and Windows Hello.

All of my impressions are as of Windows 10 build 15063, paired with an iPhone 7 Plus. For more, see the 10 best features coming to Windows 10.

With the recent release of Creators Update, you’ll be now able to lock your PC with a Bluetooth-paired smartphone or a device. This Dynamic Lock uses the Bluetooth signals to lock your PC. If the strength of the Bluetooth signal is weak, it assumes you have stepped away and locks your Computer. Let’s see how this works.

Pair your Computer with Your Smartphone

First, you need to pair your phone with your computer via Bluetooth before you enable the Dynamic Lock. You have to pair your phone and check the signal strength of the Bluetooth, Dynamic Lock doesn’t do this by itself, you have to do it.

Put your smartphone’s Bluetooth ON to start pairing. To do this on an Android and iPhone, go to Settings and then Bluetooth. Your phone can be discovered if your Bluetooth is on. Now go to your PC and start the process of pairing. To do that go to Setting and then, Devices and then Add Bluetooth or other devices. Here, click Bluetooth to pair your smartphone with the Windows 10 computer. It takes some time to list the Bluetooth devices. You’ll be able to see your smartphone in the Bluetooth devices list if it is discoverable. Click your smartphone and when prompted, enter the PIN which should be matching on both your computer and phone. Once the pairing is complete, you’ll be informed.

Enabling Dynamic Lock

To enable “Dynamic Lock”, go to Settings, then Accounts and then Sign in options, now scroll-down until you find Dynamic Lock. Now, tick the box which says ‘Allow Windows to detect when you’re away and automatically lock the device’. If you are unable to tick-mark the box, your phone isn’t paired with your computer yet using Bluetooth.

If you don’t see the Dynamic Lock option at all, then your PC hasn’t been upgraded with Creator’s update.

There is no other option for you configure Dynamic Lock on Windows 10 PC. You can’t even choose which device Dynamic Lock depend on to connect through Bluetooth, though it would use your smartphone. For example, if your PC is paired with two Bluetooth devices at that particular moment and you walk away, you wouldn’t know which device the Dynamic Lock has used to lock your PC.

The official document from the Microsoft tells that Dynamic Lock needs a smartphone to be paired with. But Dynamic Lock can be paired with other devices with Bluetooth like a smartwatch or a headphone. But don’t rely on them. Microsoft says not to pair Bluetooth devices with Dynamic Lock, which you leave them near your computer at all the time like keyboard, headphones etc.

Check If Dynamic Lock Is Working

To check if the Dynamic Lock really locks your PC when you step away. Simple, take your phone and walk away from your PC. This will automatically lock your computer after 30 sec or a minute. Remember that, the time to lock your PC by Dynamic Lock depends on the strength of the Bluetooth signal. So the time to lock your PC may vary depending on the device.

Your computer even gets locked after a minute you turn-off the Bluetooth on your smartphone. This is because your computer cannot detect the device anymore. When you are back to your computer, you have to manually sign in. Dynamic Lock does not unlock automatically as soon as it recognizes your device.


To enable Dynamic Lock on your Windows 10 PC, you have to upgrade to the Creators Update. If and when you’ve lost files after an auto update, here is a software that helps you to get your lost data back after Windows 10 auto update. It’s an easy to use tool which retrieves almost 300 file types.

Also Read:

  1. Don’t Wait For Windows 10 Anniversary update, Get it now Manually
  2. Best way to Convert Dynamic Disk to Basic Disk
  3. How to Sync Windows 8 with Android Phone?
  4. Why does my Android phone keeps rebooting automatically?

Senior Editor, Content Analyst and a fan of exceptional customer service. John develops and publishes instructional and informational content regarding partition management, Windows hot-fixes, data management and computer troubleshooting.

As a tenured data recovery specialist, John shares exceptional insights and blog posts about data loss and data recovery across any storage device. With 8+ years’ experience in writing for Data Recovery for both Mac OS and Windows OS computers, he is an avid learner who always wants to polish and simplify the data recovery process. John passes his free time playing Chess and reading Science Fiction novels.

By Bryan Clark 08 May 2019

One of the new features in April’s release of the Windows 10 Creators Update was Dynamic Lock. For those that work in a public space, or perhaps those with roommates, Dynamic Lock pairs with your phone and locks down your computer when you leave it unattended.

1. On your PC, click the gear icon in the Start Menu and select settings.

2. Click Devices.

3. After ensuring Bluetooth is first toggled on, click the + button for Add Bluetooth or other device.

4. Click the Bluetooth icon.

5. Click the appropriate device, and then wait for the PC and mobile phone to pair. You may have to accept a prompt or two to complete the pairing process, depending your phone.

6. Click the back button in the Settings menu and select Accounts.

7. Select Sign-in options from the left panel.

8. Scroll down to Dynamic Lock, and check the box for Allow Windows to detect when you’re away and automatically lock the device.

With that knowledge under your belt, you’re probably ready for more! Check out our walkthrough for how to password protect a folder in Windows 10 to hide files, our guide on how to delete old emails in Gmail to save space and our instructions for how to create a shortcut to a website in Chrome.

Windows 10 can automatically lock your PC when you walk away from it, keeping your information secure. If you forget to lock your device yourself, Windows will cover for you by consulting with your phone. The feature was introduced with the Windows 10 Creators Update and is labelled “Dynamic lock.”

How to use dynamic lock to automatically lock your windows 10 pc

Enabling Dynamic Lock is a case of ticking one checkbox. Head to the Settings app and click the “Accounts” button. Navigate to the “Sign-in options” page and check the “Allow Windows to detect when you’re away and automatically lock the device” option is enabled.

This turns the feature on but it won’t work straight away. Dynamic Lock functions by talking to your phone over Bluetooth to determine when you’re away from your PC. It gauges the Bluetooth connection strength with your phone to automatically lock your PC as you walk further away from it.

How to use dynamic lock to automatically lock your windows 10 pc

For Dynamic Lock to operate, you’ll need to pair your phone to your PC over Bluetooth. Return to the main menu of the Settings app and enter the “Devices” category. On the “Bluetooth & other devices” page, press the “Add Bluetooth or other device” button at the top to start setting up your PC to work with your phone. Follow the prompts to discover and pair with your phone.

With your phone paired and Dynamic Lock turned on, you can start to test the feature. You should find that walking a short distance from your computer while holding your phone will prompt Windows to lock itself. There’s a delay of one minute before your PC will lock, ensuring it doesn’t continually interrupt you if your Bluetooth signal drops or your phone loses connection. When you return to your PC, you’ll need to sign-in with your usual authentication method.

How to use dynamic lock to automatically lock your windows 10 pc

Dynamic Lock is a fairly basic security feature. We wouldn’t recommend relying on it if you’re looking for maximum protection. The one minute window in which your PC remains unlocked could be all an attacker needs to take control of the system.

Windows won’t lock the device at all if it detects it’s in use, so somebody only needs to click the mouse or start typing to abort Dynamic Lock. The feature could help keep you safe if you forget to lock your device before taking a walk or heading to a meeting. Beyond that, you shouldn’t depend on it to always hit Win + L for you.

Not sure what “Dynamic lock is not working” Please help?

* Moved from Virus & Malware

* Original title: drivers

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Replies (1) 

Thank you for writing to Microsoft Community Forums.

I understand that you get a message Dynamic lock is not working. I’ll certainly assist you with this.

Dynamic lock is a feature in Windows 10 which allows you to use devices that are paired with your PC to help detect when you’re away, and lock your PC shortly after your paired device is out of Bluetooth range. This makes it more difficult for someone to gain access to your device if you step away from your PC and forget to lock it. For more information, see Lock your Windows 10 PC automatically when you step away from it .

It could be possible that a device such as mobile phone connected to your computer is not within the Bluetooth range that is the reason you are seeing this message. In case you had your phone connected to the computer and seeing this message, to fix this, just go to Start >> Settings >> Accounts >> Sign-in options >> Dynamic lock and select Scan for device.

This will automatically detect the phone and connect it back. Make sure the device is in range and Bluetooth is turned on.

Let us know the results, we will be glad to help you further.