A computer virus is a subspecies of malware (malicious software) designed to replicate itself. That is, this program copies itself to all drives connected to your computer.

Are you worried that your PC might have a virus? If your computer has been infected, it is essential to know how to get rid of such a virus.

In this article you will learn how computer viruses work and how to remove them from your PC.

You will get answers to the following questions:

• How does a computer virus work?
• How to remove a computer virus step by step?
• How do I remove a virus from a Mac?
• How do I know if my computer has been infected?
• Can my computer get infected through email?
• How can I protect my computer from viruses?

How does a computer virus work?

Computer viruses are so named because they have the ability to replicate like real viruses. Once a virus has infected your computer, it continues to spread. If your computer is infected with a virus, it may become slower or stop working properly.

There are three main reasons why your computer might be infected with a virus.

The first way of infecting your computer is through removable media such as USB flash drives. A connected USB stick from an unknown source may contain a virus.

Hackers sometimes deliberately place USB sticks, memory cards or other removable storage media in offices or in public places (e.g. cafes) in order to spread computer viruses. It can also happen that using clean USB media transfers files from an infected computer to an uninfected one.

Another way your computer can become infected is through downloads from the Internet.

When downloading programs or apps from the internet, make sure you use a trusted source like Google’s Play Store or Apple’s App Store. Avoid downloading via pop-up windows or from websites you don’t know.

The third way your computer can get infected is through email attachments or by clicking on a link in a spam email.

Avoid opening an email from a sender you don’t trust or don’t know. If you do need to open the email, do not click on links or open attachments.

Learn how to clean computer viruses from Windows PCs and Macs in the next two sections.

How to remove a computer virus step by step?

Computer viruses are almost always invisible. It’s very likely that without antivirus protection, you won’t even realize you have a virus on your PC. That’s why it’s essential to have antivirus protection installed on all your devices.

If your PC has a virus, get rid of it with these ten easy steps:

Step 1: Download and install an antivirus scanner

Download a virus scanner or a complete internet security solution. We recommend Kaspersky Internet Security or Kaspersky Total Security. The following video guides you through the installation process:

How to install and activate Kaspersky Internet Security 2018

Step 2: Disconnect from the Internet

When removing a computer virus, it is important that you disconnect from your Internet. Finally, some viruses use the Internet connection to spread.

Step 3: Restart your PC in Safe Mode

To protect your computer while you remove the virus, restart it in Safe Mode. Don’t know how to do this?

Here’s a simple guide:

• Turn your computer off and on again.
• Once the monitor lights up, press “F8” to bring up the Windows “Advanced Boot Options” menu.
• Click “Enter Safe Mode”.
• Stay disconnected from the internet.

Step 4: Delete all temporary files

Next, use Windows Disk Cleanup to delete all temporary files.

How to do this:

• Click on the Windows logo at the bottom left of the screen
• Start typing “disk cleanup”
• Once the app appears in the search box, click on it
• In the list of files to delete, locate Temporary Internet Files
• Highlight this entry and click “OK”
• Confirm this process with “Delete files”

Some viruses are designed not to run until you start your PC. Deleting the temporary files can already help to remove this type of virus. However, it should not be relied upon and it is advisable to follow the next steps as well.

Step 5: Run a virus scan

Now is the time to run a virus scan using your chosen antivirus or internet security software. If you are using Kaspersky Internet Security, click Scan.

Step 6: Delete or quarantine the virus

If a virus is found, it can damage multiple files. Select the Delete or Quarantine options to remove the virus. Scan your PC again to make sure no other threats exist. If other threats are found, delete or quarantine them as well.

Step 7: Restart your computer

Now that the virus has been removed, you can restart your computer as normal. Safe mode is no longer needed.

Step 8: Change all passwords

To protect your computer from further attacks, you should change all your passwords. This is only strictly necessary if you have reason to believe that malware has captured your passwords. But here, too, it is better to be safe than sorry.

If you’re not sure what the function or target of the virus you found was, you can check your antivirus vendor’s website or their support team for more information.

Step 9: Update your programs, browser and operating system

Updating your software, browser and operating system reduces the risk that flaws in the old code will be exploited by criminals to install malware on your computer.

How do I remove a virus from a Mac?

If you own a Mac, you may think that your computer cannot get infected. Unfortunately, that’s a misconception. In fact, there are fewer viruses targeting Macs than Windows PCs, but they do exist.

Some Mac viruses are designed to trick the user by pretending to be an antivirus program themselves. If you accidentally download something like this, your computer may become infected as a result. Three examples of this type are: “MacDefender”, “MacProtector” and “MacSecurity”.

If you suspect your Mac has a virus, get rid of it with these six easy steps:

• Quit the potentially infected program or app.
• Go to your Mac’s Activity Monitor and look for known viruses such as “MacDefender”, “MacProtector” or “MacSecurity”.
• If you find such a virus, click “Force Quit” before closing Activity Monitor.
• Next, go to the “Applications” folder and drag the file to the “Trash”.
• Don’t forget to empty the trash afterwards to permanently remove the virus.
• Make sure your apps and programs are up to date to benefit from the latest security patches.

To ensure nothing has been forgotten and to protect your Mac in the future, consider installing and activating an antivirus solution. We recommend using extensive Internet security solutions such as Kaspersky Total Security.

How do I know if my computer has been infected?

There are numerous signs that indicate that your computer may have a virus.

First: Is your PC running slower than usual? If everything is taking longer than usual, your computer may be infected.

Second, look out for apps or programs you don’t recognize. Be careful if an application appears on your computer that you haven’t downloaded.

Check your computer for software you do not recognize and uninstall it if necessary. If you are unsure, you can research the program on the Internet. Then run a virus scan with your antivirus scanner or use a comprehensive Internet security solution to look for threats. Pop-ups that appear despite the browser being closed are a prime example of a virus. If this happens, remove the virus immediately using the steps above.

Another sign of an infected computer is apps or programs that behave strangely. If applications crash suddenly and for no apparent reason, your computer may have become infected.

Finally, viruses can also cause your computer to overheat. If this happens, scan your computer with an antivirus scanner or a comprehensive internet security solution.

Can my computer get infected through an email?

Yes, your computer can get infected via email – but only if you open the attachments or click on the links in a spam email.

Simply receiving spam emails cannot infect your computer. Just mark these emails as “spam” or “junk” and make sure they’re deleted. Most e-mail providers already do this automatically (e.g. Gmail), but should such an e-mail still end up in your inbox, simply mark it as “spam” yourself and do not open it.

How can I protect my computer from viruses?

The following are some of the most important measures you can take to protect your computer from viruses:

• Use antivirus software or a comprehensive Internet security solution such as Kaspersky Total Security. For your Android smartphones you can use Kaspersky Internet Security for Android
• Find out more about apps and programs by reading their user reviews
• Check the developer before downloading and installing an application.
• Only download applications from trusted sites.
• Find out how many times an app or program has already been downloaded. The more often, the better.
• Check and question the permissions an app or program needs.
• Never click on unsafe links in spam emails, messages or on unknown websites.
• Do not open attachments in spam emails.
• Keep your programs, apps and operating system up to date with updates.
• Use secure VPN connections such as Kaspersky Secure Connection.

in public WiFi networks

• Never connect unknown USB sticks to your computer.

With these security solutions you can carry out an extensive virus scan

Kaspersky Internet Security

Kaspersky Total Security

Kaspersky Security Cloud

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