Online privacy is an issue of growing importance to internet users everywhere.

Increased online aggression from authoritarian regimes like Communist China and Russia, a growing tendency towards online surveillance from western democracies, and the rising number of hackers operating in the online shadows have made the internet an increasingly insecure place.

With governments tending to be the cause of these problems rather than the solutions, people have been increasingly left to protect themselves online. This has seen a huge growth in users of VPNs and other online security tools.

With a suite of online security tools at your disposal, it is possible to keep the myriad of online threats at bay. But nothing is 100% foolproof and even with a VPN and other tools in place, it is still possible for your device to compromised.

In this guide, we are going to take a deep-dive into this issue.

How can you tell if someone else has managed to access your device?

How can you tell if your device is being controlled by someone else?

How can you tell if a hacker or a hostile government is siphoning off your data?

It sounds like the stuff of sci-fi movies but actually, these scenarios are all too real and are happening around the world every day. If you want to know whether you have fallen victim to it and learn how to stop it, this is the guide for you.

Part One: Who might be looking at my computer or mobile device

In the first section, we will take a closer look at who out there might want to take over your device or look at what you are doing online or on your computer.

The natural assumption is that this will be hostile foreign agents who are either snooping on you directly or harvesting data from all sorts of different people.

As you will see, this is a possibility, but it is also quite likely that the culprit could be someone much closer to home.

Hackers

Hacking is a catch-all term for all sorts of different online operatives.

Hackers can be goodies who test out software to find vulnerabilities and claim rewards. They can be working for governments in free and democratic countries to take on hostile countries that pose a threat to them and their own people.

They could also be working for authoritarian regimes for precisely the opposite purpose.

Equally, they can also be working for organised criminal gangs or even as lone wolves, with the sole objective of stealing valuable content and making money.

Either way, accessing your device is an excellent way for a hacker to get what they want. Once they are inside your computer, they can access all your online passwords, see what services you use, copy bank and credit card details, and much more.

They can either download data regularly or just collect the information they need and then depart. Equally, they could also put malware or ransomware onto your device to hoover up data regularly or lock your data and demand a ransom for its release.

Hackers can pose a threat to any internet user and are something we all need to be aware of and protect ourselves against.

Government Surveillance

Government surveillance agents are in many ways a type of hacker but instead of looking to steal money or other assets, they are far more likely to want to monitor what you are doing online.

There are various reasons why they might want to do this.

You might be a suspect in a criminal matter or be considered a threat to national security in some way. You might have connections to someone else who falls into these categories.

Depending on the type of government you live under, you might be surveilled because of your political activity, your job if you are in a profession such as journalism and the law, or just because this is how the regime that runs your country controls its people and maintains its grip on power.

In some countries, you are obliged to download software which allows governments to monitor your online activity. In other countries, they are a tiny bit more subtle than that but surveillance is still an everyday occurrence.

If you live in a free and democratic country, you might think this is less of a concern for you. But think again.

As Edward Snowden revealed back in 2013, the US Government routinely collects and monitors the online activity of every US citizen.

Here in the UK, the Investigatory Powers Act requires UK ISPs to collect the data of every British internet user for at least one year and hands access to this data to an astonishingly wide selection of public bodies.

Government surveillance is a reality for everyone, everywhere and accessing your device is just one of the many techniques they have at their disposal.

Family members

It is a commonly known fact that you are far more likely to be killed by someone you know than a random stranger. And the truth is that there is a pretty high chance that if your online device has been compromised in some way, it is a family member who is responsible.

There are all sorts of reasons why a family member might want to access your device.

Perhaps your husband, wife, or partner, suspects you of infidelity and is looking for evidence. Maybe your parents are checking up on what you are doing online.

Perhaps someone wants to use your Amazon account to buy that book they have been after for ages.

Equally, perhaps you just left your device open and unlocked on the kitchen table while you popped to the shops or left a list of your passwords lying around in the living room and someone decided to have a snoop.

A lot of people won’t mind family members looking at their devices but if your device has been accessed, there is a pretty decent chance it will be a family member who is responsible.

A boss or work colleague

If you have a work computer or a work smartphone, there is a good chance that either your boss or your company’s IT department will be able to access that device.

There are all sorts of legitimate reasons why this might be the case.

Your IT department might need to update software or run security scans on a regular basis. You might have a shared drive with information that your boss or even other colleagues need to access.

But there could be more underhand reasons why they might want to access your device too.

Perhaps you are suspected of leaking information to a rival. It is possible that your work has been below par and they want to see what you have been doing. Maybe someone has used your account to access content that they shouldn’t have on the corporate intranet.

Often employers are well within their rights to access work-issued devices.

But if you are using a work device for personal matters, there can sometimes be a cross-over. And you don’t want your employers seeing private and confidential information unnecessarily.

Teachers and University staff

If you are still at school or in University, it is possible that the IT staff or even the teaching staff might be able to access any devices that have been issued to you from there.

The reasons for this are likely to be similar to the previous section. Either they are monitoring what you are using the device for or accessing shared content in order to mark or moderate it.

Either way, if they do have access, there is the potential for them also to see any personal and private data or activity you have stored there and for many people that is far from ideal.

Part Two: How to check to see if someone is using my computer or mobile device

The big problem with the issue of a hacked device is how to tell if your computer has been hacked or not.

Some hackers are loud and proud about their activity and leave malware or ransomware that tells users immediately that they have been hacked. But it is in the interests of others to be subtle.

If they want to monitor your activity over a sustained period, they will need to be subtle and hope you don’t notice they have been there.

But the good news is that there are various different ways that you can check an internet-enabled device to see if someone else has been using it.

In this section, we will outline some of the simplest and most effective.

Check logins on Windows

A simple way to check whether or not somebody else has been using your computer is to check the login records to see when your device has been logged into.

On Windows devices, this is relatively simple to do although it should be noted that full login auditing is only available with a subscription to Windows Professional.

Still, Windows Home lets you see a record of successful login attempts and this should be enough to alert you to any suspicious activity on your device.

Different versions of Windows may have slightly different methods of doing this but all broadly follow the same process as for Windows 10, which is outlined below.

1. Right-Click on the Start button.
2. Click on Event Viewer.
3. Look for Events with Event ID: 4624, Task Category: Logon.
4. Double-click on an event for further details. This should include the precise time of a login.

If you see any logins at a time you know you weren’t logging in, this means it is highly likely that someone else has accessed your Windows device.

It is also possible to see if anyone else is remotely logged into your Windows device right now if you have Windows Professional. To do this, just follow these couple of steps:

1. Right-Click on the Start button.
2. Click on Command Prompt.
3. Type query user.
4. Click Enter.

You will see a record of all users currently logged into your device. If there is more than one user listed, you are not alone!

Check logins on Mac

If you are using a device running macOS, there is a different process you will need to follow to check whether anyone else has been logging into your device without your knowledge.

Here is a step-by-step guide for you to follow:

1. Open your Mac device.
2. Go to Applications.
3. Click on Utilities.
4. Click on Terminal.
5. Type last (lower-case ‘l’) and press Enter.

You will now see a list of all recent logins alongside a timestamp which details exactly when that login happened. It will also detail the name of the user that logged in so you can see who and when has been accessing the device.

As with Windows devices, you can also check to see if there is anyone logged into your device right now. To do this, just follow this similar process:

1. Open your Mac device.
2. Go to Applications.
3. Click on Utilities.
4. Click on Terminal.
5. Type who (lower-case ‘w’) and press Enter.

This will list the name of everyone who is logged into your device right now. If there is more than one name there, that means someone else is logged in as well.

Check logins on Linux

If you are a Linux user, never fear because there is a method for you to check your device login history as well.

The process with Linux is not dissimilar to the Mac method, but there are some subtle differences worth noticing. Here is the process for Linux devices:

1. Open your Linux device.
2. Go to Show Applications.
3. Click on Terminal.
4. Type last (lower-case ‘l’) and press Enter.

Like a Mac, Linux will show you a list of recent logins along with details of the time of the login and who the user was.

If you want to take a look at who has been logging into your device, the process follows similar lines:

1. Open your Linux device.
2. Go to Show Applications.
3. Click on Terminal.
4. Type who (lower-case ‘w’) and press Enter.

If any usernames you don’t recognise show up, that means someone else is logged in too.

Check activity on iOS devices

If you have an iPhone or iPad, it is possible to check the login records but this information is usually not quite as revealing as it is on a computer.

This is because we are all using our mobile on a regular basis and they are generally kept logged in to most things around the clock.

But while login data might not be very revealing, the way to check to see whether someone else is using your device is to look at the activity data.

Devices that run on iOS will keep a log of every time you use an app, open an app, use your browser and so on. By checking this data, you can compare activity times with the times you have been using your device.

If you know you were asleep or perhaps in a meeting or a class when some activity took place, you can deduce that someone else must have accessed your device.

Checking activity logs on an iOS device is another fairly simple process but it does require you to connect to a macOS enabled device to do it. Just follow these few simple steps:

1. Unlock your iOS device.
2. Connect your iOS device to your macOS computer using a USB cable.
3. Open the Console app on your macOS device.
4. Click on Applications.
5. Click on Utilities.
6. Click on Directory.
7. Click on the relevant device from the list on the left-hand side of the screen.

You will then see a log containing information about all of your recent activity on your mobile device. If you spot activity that you don’t recognise, there is a good chance someone has been accessing your device.

It is also possible to use this to check the activity logs on an iWatch too but you will need to have synced the iWatch with your iPhone first.

If you see no data listed, the chances are that your iPhone or iPad is not unlocked. It needs to be for this process to work, so just unlock it and go through the steps again.

Check activity on Android devices

Android devices are slightly different to iOS ones and there are different ways of checking activity. You can check phone usage statistics, recent activity on the device, or recent activity on the Google account connected to the device.

For the purposes of this guide, it is the device activity which is most useful and you can check this using the following simple steps:

1. Open your devices Settings app.
2. Click on Manage your Google Account.
3. Click on Data and Personalisation.
4. Under the Activity and Timeline tab, click on My Activity.

You will see a detailed list of your device activity which is organised by day and time, making it easy to identify if your device has been used at a time when you weren’t using it.

Check recently modified files

If your device has been compromised, one of the most likely activities that a hacker will undertake is to either install new (malicious most likely) software or corrupt existing software on the device.

Either way, a good way to check whether someone else has been messing about with your device without your knowledge is to look at the recently modified files.

You should know which apps you have recently downloaded, updated, or modified. So, if any other apps crop up on this check, it can be a tell-tale sign that someone else has access to your device.

Checking for modified files is another relatively simple process but it does vary from one device to another, so here is a rundown of how to do this check on all the main devices:

Windows

1. Open File Explorer.
2. Click on the View tab.
3. Select the Details option in the toolbar.
4. Right-click anywhere in the column header.
5. Click on More.
6. Scroll down the menu to the various date options and select Date Accessed and Date Created.
7. Click OK.

In File Explorer, this information will now be visible and you can search for apps or other data as you see fit.

macOS

1. Navigate to the Documents folder in the Finder.
2. Press Command+F.
3. Set the search conditions to ‘Last Modified Date’.
4. Enter the number of days you want to search.

This will generate a list of files that have been modified, in reverse chronological order for the period you have specified.

You can check to see what files were modified and when and compare this with the time you were using your device.

Linux

In Linux, you can search for recently modified files using the Find command. Simply enter the following command:

• find . -mtime -n

In place of the n, enter the number of days you want to search back through. For example, if you wish to search for the past two days, enter mtime -2. This will generate a list of all files that have been modified in the past two days.

Check browser history

It is quite likely that a hacker or even a family will need to get online when they are using your device and they are likely to use a browser already installed on your device to do this.

If they are being really careful, they might remove all trace of any searches or websites they have visited from your web browser history. But often they aren’t that careful and this can be another tell-tale sign that someone has accessed your device.

There are many different browsers available but most of us will use one of just a handful, so here is a brief rundown of how to check the browser history on the most commonly used web browsers.

Google Chrome

1. Open Chrome.
2. Click on More in the top right of the screen.
3. Click on History.

Mozilla Firefox

1. Open Firefox.
2. Click on the Library button.
3. Click History.
4. Click the Show All History bar at the bottom of the list (if you want to see more than the most recent history items).

Safari

1. Launch the Safari app.
2. Click on History.
3. Click on Show all History.

Microsoft Edge

1. Open Edge.
2. Click on the Hub button.
3. Click on the History button (with a clock face on it).

Opera

1. Open Opera.
2. Click on the Opera Menu button in the top left of the screen.
3. Click on History to open the history tab.

All of these History lists should include details of the date and time that a website was visited and allow you to search through to see what sites were visited when.

If there are listings for times when you know you weren’t using your device, this means that someone else must have been.

Part Three: How to stop people using my computer without permission

So far in this guide, we have explained why people might want to be using your internet-enabled device and outlined who they might be.

We have also given you several different methods to check and see if someone actually has been using your computer or other devices without your permission.

But what should you do if these methods have confirmed your worst suspicions?

If you suspect the person responsible is someone you know, such as a family member or a work colleague, the easiest way to deal with the problem is to confront them about it and find out what they have been doing and why.

If it is a work colleague or someone in a school or a university, it is quite likely that there are complaints procedures that you can follow. Your HR team, IT department, or other helpful body should be able to offer you advice and guidance on dealing with the issue.

But regardless of whether you know the culprit or not, you probably still want to take action to stop them from being able to access your device again.

In this section, we are going to offer a series of recommendations about how to do this. Some of these tips are simple actions that you can do yourself in a few moments.

A few will be most effective with the help of additional security software. But if your device has been compromised, you might well think that this software is well worth investing in.

Change Passwords

If your device is not already protected by a login password, it should be. If it has one, you need to change it immediately.

Having a strong password is essential to protect devices and online accounts from being compromised by hackers.

If you have shared your password with family or work colleagues for some reason, changing it should prevent them from being able to use your device without permission.

It is good practice to change the passwords to your accounts on a fairly regular basis anyway. But if you do suspect someone of using your device, this is a simple way to stop them.

When you choose a new password, it is worth taking a moment to make sure you have chosen one that is strong and secure and which your family or work colleagues won’t be able to guess, never mind a hacker.

When choosing a new password, there are some simple rules you should be following, which I’ll cover below.

Don’t use weak passwords

In 2019, the National Cyber Security Centre published its first annual UK Cyber Survey. As part of this, they also produced a list of the 100,000 most common passwords that people use.

A hacker has breached every single one on this list at one time or another.

It is worth dipping into this list or seeing if your passwords are on there or not. Just to whet your appetite, the top 5 were:

• 123456
• 123456789
• qwerty
• password
• 111111

The report also warned against using things like family names, the names of favourite pop groups, football teams, fictional characters, actors, and so on.

Passwords like these are often easy to guess, especially if someone knows a little bit about you. They are also often quickly broken by hackers using specialist password-cracking software too.

Take a look below at the simple rules you need to follow when choosing a secure password.

Don’t repeat passwords

Another bad habit many people have is using the same password for multiple accounts.

This makes the life of a hacker very easy as they only have to crack one password and they can access several accounts or devices. Never use the same password twice is a simple but important rule.

How to choose a secure password

When you are choosing a new password for a new account, there are a few simple rules you should be following:

• Avoid common words and phrases like ‘password’ and the others listed above.
• Don’t use personal details like family names and dates of birth.
• Make sure all passwords are at least 8 characters in length. The longer the password, the harder it is to break it.
• Use a combination of upper and lower case letters throughout the password.
• Always use numbers in your password somewhere.
• Always use symbols such as @, !, and & in your password.

The ideal password is a random selection of upper and lowercase letters, numbers, and symbols.

These are often not used because people find them too hard to remember. But this is where a Password Manager can help (see below).

Another theory some experts prefer is to put together three unrelated words that are easy for you to remember but not for a hacker to guess. If you can get some numbers and characters into this format, so much the better.

For example, things like:

• M0nk3yG@rdenJer3my (Monkey-Garden-Jeremy)
• H@rr1sChurchF0ur (Harris-Church-Four)
• l!v3rp0olB3tt3r4r53n4l (Liverpool-Better-Arsenal)

Don’t write down passwords

If you leave a list of passwords lying around, it is quite possible that this is how a family member or a work colleague might access your device.

If you find it hard to remember all of your passwords, write a list of hints instead of the passwords themselves to help you remember without giving them away to others.

Even better would be to use a Password Manager.

It’s also worth remembering that password recovery questions are likely to have answers that family members will know. Mother’s maiden name anyone? Your sister, father, grandparents will all know this.

What is a Password Manager?

A password manager is an online tool that solves the problem of trying to remember all these complex passwords.

It stores all your passwords using encryption to protect them and allows you to access them by remembering a single master password.

Password managers can also generate randomised and secure passwords and auto-fill website and app logins so you don’t have to type your passwords in.

They offer a simple solution to one of the genuine weak points of online security. If you are worried about devices or accounts being accessed by others, a password manager can help you to prevent that.

If you are wondering which password manager you can use, here is a rundown of our top 5 recommended password managers:

LastPass

LastPass is one of the best known password managers and also one of the best.

It lets you store all your passwords and, if you wish, credit card details and other sensitive details. You can generate new and strong passwords automatically and even set yourself reminders to refresh these on a regular basis.

LastPass has an excellent autofill feature, offers high-quality security, and you even get all this for free version, although use is limited to a single device.

LastPass can be downloaded onto Windows, Mac, iOS, and Android devices and offers apps that are really well designed and very easy to use.

DashLane

DashLane is another password manager that has been around a while. It has a limited free version too but if you want to get access to all the features, you will need to upgrade to the premium package.

DashLane stores all of your passwords securely and lets you access them quickly. It can auto-fill passwords into any website or app, generate secure passwords for you, and store other sensitive data too.

DashLane is even able to search the Dark Web to see if your passwords have been leaked anywhere and inform you if they think you have been hacked.

DashLane is available for Windows, Mac, iOS, Android and Linux devices and it also comes with apps that are incredibly user-friendly.

1Password

1Password is a powerful password manager that remembers all your passwords and lets you log into websites with just a single click.

It is a user-friendly app that is easy-to-use and there is a free trial available. It comes with several bonus features including supporting Two-Factor Authentication and authenticator tools (see below for more on these).

1Password supports most major devices and even has a range of browser extensions available as well.

KeePassXC

KeePassXC is another excellent password manager but this one is best suited to more experienced users.

It offers the additional security of letting you self-host your password database. That means all your passwords are encrypted and securely stored on your device rather than an external server.

This is a great feature but it does make things more complicated. But if you are up to the challenge, KeyPassXC is another good choice.

Password Boss

Password Boss is a cloud storage Password Manager that offers a popular free version. It is one of the most secure password managers available and comes with all the main features of the other ones on this list.

A big advantage with Password Boss is that it keeps all your passwords in a secure cloud storage facility.

This makes it easier for you to access them from anywhere and also means your passwords are not stored on any one individual server or device that could be compromised.

Password Boss comes with plenty of features but it is still fairly simple to use and available on most devices.

Two Factor Authentication (2FA)

Using secure passwords, changing them regularly, and employing the help of a password manager will go some way to making your device more secure and helping to stop unwanted people from accessing it.

But there are ways to make it even more secure and one of these is to use Two Factor Authentication (2FA).

2FA is a technique to add an extra layer of protection in addition to your new password. If you are using 2FA, and your password ends up in the wrong hands, your device or account still should be secure unless someone also has access to your smartphone or another device.

2FA involves having to enter a separate code in addition to your password in order to access a device, site or service. This code will usually be sent separately to your smartphone or email account and you will not be able to access your device until you enter this code too.

You can also use physical devices for 2FA.

If you want to learn more, you can read our complete two-factor authentication guide.

Biometric Identification

While 2FA is probably the most commonly used type of additional security, another method that is growing in usage quickly is biometric identification.

This is especially common in many mobile devices now, which have the option of using a fingerprint scan or even a facial image to unlock and access the device.

Biometric technology does come with some serious privacy dilemmas, but it does prevent hackers and others from easily accessing your devices and accounts without your knowledge or permission.

Physical Keys

Another slightly more traditional form of 2FA involves physical keys such as the YubiKey.

Physical keys generate a one-time code every time you want to log-in to a device or an account. You have the physical key in your possession to log into this account.

This can be inconvenient but it does add an extra layer of security and means that if someone does try to access your device without your knowledge, they will be unable to do so.

Always log out of accounts and devices

It is quite common for people just to close their laptop lid or walk away from their device and not think about logging out of everything. But this can be a big risk if there is someone else around who might want to gain access to your device.

If everything is left logged and open, it is effortless to gain access and start going whatever you want to on the device. But log out of everything and shut down devices properly and you are making this much harder.

We would go so far as to say that if you log out and shut down, you are going to prevent all but the most technologically-savvy hackers from being able to access it.

Logging out and shutting down is an excellent habit to get into.

Installing Antivirus software

Antivirus software is a key tool for stopping remote hackers from accessing your device and stealing sensitive information. A common method of doing this is to download malware onto your device.

This might allow them to control the device or monitor your activity. Keylogging malware is prevalent at the moment. This records every keystroke you make and uses it to hoover up passwords and see what you are doing on your device.

Also growing in popularity is ransomware which encrypts your data and demands you pay a fee to be granted access to it again.

The best way to protect against this type of attack is to have a good quality antivirus programme installed on your computer.

Make sure you choose a reputable one and be sure to give it permission to update its definitions automatically to ensure you always have the best possible protection.

There are lots of good quality antivirus tools on the market, but here is our pick of the top 5.

Bitdefender Antivirus

Bitdefender Antivirus is an excellent anti-virus programme. It is regularly updated with the latest definitions so you should always be protected against the latest threats.

Bitdefender Antivirus is simple to use but packed full of features if you want to personalise it a bit more.

The free version of Bitdefender is more than sufficient for most regular users. Still, if you want more, you can upgrade to Bitdefender Antivirus Plus which is even more secure and very reasonably priced.

Bitdefender Antivirus lets protect up to 10 devices.

Windows and Mac devices are included in this but if you want to protect iOS or Android mobile devices, you will need Bitdefender Total Security, which is also excellent value for money.

Avast Antivirus

Avast is the best known free antivirus programme on the market right now. Its lightweight software means it takes up less space on your device but it still offers everything that its competitors do in terms of protection.

Avast does offer a Premium Security suite if you want to pay a small fee. This bundles together various other bits of Avast software including a VPN.

However, we would generally advise against this as a bundled VPN such as this in our opinion, is usually not as effective as a dedicated VPN.

But for antivirus protection, Avast is up there with the very best.

Norton Antivirus Plus

Norton Antivirus has been around for years and remains one of the best anti-virus tools on the market right now. It has a huge range of virus definitions that are regularly updated so you should be protected from any new viruses that emerge.

The interface on this tool is not the most user-friendly we have encountered, but it doesn’t take too long to get used to. Sadly there is no free version of Norton Antivirus available but the prices are fairly reasonable.

Having said that, you will need a new subscription for every device so if you use multiple devices and want to protect them all, this can quickly add up.

Trend Micro Antivirus +

Trend Micro is another name that has been around the antivirus scene for some time and their experience is in evidence in their Antivirus + software. This software is highly rated by security experts and its levels of protection it offers are up there with the very best.

However, Trend Micro Antivirus + is quite resource-intensive and is likely to slow down your device.

This annoying trait can cause some people to switch their anti-virus software off, which is never a good idea. Trend Micro does also offer a higher-spec Internet Security and Maximum Security software if you want to spend a bit more too.

Sophos Home

Sophos Home is able to protect up to ten devices and offers an extremely user-friendly interface.

Its antivirus protections are robust but perhaps not quite as comprehensive as some of the others on this list. But for basic online users, it will be more than sufficient.

The free version of Sophos Home is good enough for most but if you want more robust protection, you can also opt for Sophos Home Premium which is priced very affordably.

It should be noted that even with an antivirus tool installed and kept up-to-date with the latest virus definitions, there is no 100% guarantee that you are protected from all malware and other malicious programmes.

But they will protect you from most and this will give you the best possible chance of preventing hackers from compromising your device.

Encrypt your Hard drive

A good way to prevent even the most technologically sophisticated hacker or state agent from being able to access your device and read your files is to enable full-disk encryption.

This will encrypt everything on your device and stop anyone who doesn’t have the encryption key from being able to access your hard drive while not in use by yourself.

Enabling full-disk encryption is not as difficult as it might sound. But there are different ways to do it and various tools to use, depending on what device you are using.

Here are the most straightforward for common devices.

Windows

If you are a Windows 10 Pro user, all you have to do is turn on BitLocker full-disk encryption which is included with your operating system.

You can do this quickly and easily by following these few simple steps:

1. Open Control Panel.
2. Click on BitLocker full disk encryption.
3. Select Turn BitLocker On.

This will enable BitLocker full-disk encryption and your hard drive will be protected.

If you use another version of Windows, your best bet is to use an open source hard drive encryption tool such as VeraCrypt. This is relatively easy to do, just follow the onscreen instructions on this link.

macOS

If you have a device running on macOS, you also have an inbuilt hard drive encryption tool already installed and ready to go.

It is called FileVault and you can enable it by following these simple steps:

1. Go to System Preferences.
2. Click on Security and Privacy.
3. Select the FileVault tab.
4. Select Turn on FileVault.

This tool will then be enabled and your hard drive protected.

Linux

All devices running Linux will have a built-in dm-crypt full-disk encryption program. This works fine although some people prefer to combine this with Linux Unified Key Setup (LUKS) key management tool which is a bit more flexible.

As with many things on Linux, getting this set up is a bit more complex, but there is a useful guide you can follow here.

Use a webcam / anti-theft app

One final option that you may want to consider if you suspect that a family member or work colleague is accessing your device without your permission is to set up a camera or use another type of security tool to try and catch them in the act.

Hidden cameras are relatively easy to set up these days but be careful you are not breaching any privacy laws before you do so.

Another clever tool worth considering is Lockscreen Pro. This simple tool takes a photograph using your device’s webcam every time someone logs into the device. It will even take a snap if they try to log in and fail to do so.

That means you can implement all of the security recommendations we have offered in this guide and still catch the culprit in the act. It’s a win-win situation for you!

Use a webcam cover

As equally as important as capturing local users from using your devices is thinking about blocking your webcam from users who may access your devices remotely.

There have been numerous stories of laptops and other devices being infected with malware that allows perpetrators to enable the webcam at will without alerting the owner of the device.

Covering your webcam can be as simple as placing a small piece of sticky tape over it or using an inexpensive slider style cover.

Conclusion

If you suspect that someone might be using your device without your permission, there is a good chance you could be right. There are lots of people who might want to do this, for a variety of reasons and in this guide, we have highlighted the most likely culprits.

Finding proof that you are not just being paranoid but your device really is being used by someone else is tricky but as we have also explained there are several ways that you can check.

And what to do if your suspicions are proved to be true?

We have made some recommendations here, including strengthening passwords, using 2FA, and using a strong antivirus programme.

Hopefully, this guide has all the advice you need to keep your device secure and stop any unwanted intruders.

Have you had a problem with someone using your device without your permission? Did our recommendations help you find out who it was and stop them from doing it? Do you have any tips for other readers that we haven’t mentioned in this guide?

If so, please do share your thoughts in the comments section below.