Computer Security Guide

Understanding how to keep your computer secure is very important because it helps to protect you against viruses, malware and hacker attacks. If you have sensitive information stored on your computer, or you do online banking then it is even more important because your personal data is at risk from hackers.

Even if you don’t have any confidential information on your computer, it is still important to have security measures in place because a virus can slow down your machine considerably.

The mindset of a hacker

Before you think about how to protect yourself from hackers and computer viruses it is important to understand the mindset of a hacker. Additionally, it is important to understand what viruses are and why they are produced.

More often than not, hackers are part of an organised crime network. They are serious criminals and they are in this game to make serious money – sometimes this can be hundreds of thousands of pounds.

How do hackers profit from viruses?

  • Harvesting information from your computer – For example, some viruses hide on your computer and collect valuable information such as software license keys and bank details
  • Ransom demands – Hackers will often use a virus to encrypt all of your data, making it inaccessible, and then demand a ransom in return for the decryption key.
  • Botnets – Hackers use viruses to take control of your computer. When they have control over hundreds of thousands of computers they can use all of the resources to carry out attacks on large corporations.
  • Masking their identity – Hackers can use an infected computer to carry out more serious attacks, masking their real identity
  • Bank fraud – using key loggers, hackers can steal your details when you are using online banking

These are just some of the activities that hackers will be working towards when they make and distribute viruses.

It is very rare for hackers to carry out a targeted attack on an individual. Rather, hackers will target computer users on a massive scale – often targeting millions of users at a time – and they are looking to make serious money from doing this.

How can you tell if you have a virus?

There are a couple of common symptoms of a virus and looking out for these will give you a good idea as to whether or not your computer has been compromised:

  • Popups – The most common symptom from a virus is internet popups – you can spot these as they normally contain inappropriate content and they pop up on your screen without you clicking on anything. Viruses often create these popups in the form of advertising and the hacker will earn money for every click that you make on the ad.
  • Ransom demands – Some of the more destructive viruses will make their presence clear to you often in the form of a popup message demanding money in exchange for allowing you back into your computer.
  • Slow performance – a less obvious sign that you have a virus is slow computer performance. When a virus is running in the background it will often drain your computer’s resources and make everything else slow. In addition, sometimes viruses simply don’t work properly, and this will produce performance problems and error messages. If your computer is slower than normal, it is a good indication that you may have a Trojan virus.

Where do viruses come from?

Understanding the most common source of viruses will help you in avoiding them in the first place.

Without a doubt there are two main sources for viruses and other malware:

  • The Internet – The internet is one of the most common locations from which you can inadvertently download a virus. Viruses normally come from lesser-known websites – for example when you are searching for information on Google, if you visit a random site within the results, it is more likely to contain a virus than a well-known site like Wikipedia.
  • Email – Email is definitely the most common source of viruses. Emails are very easy for hackers to “harvest” meaning they can get hold of your email address even if you have never actually given it to them. Email is also a cheap way for hackers to reach millions of people – hackers can buy a list of millions of emails online for next to nothing and they can send viruses to these addresses at an alarming rate.

How to protect your computer from viruses

You have the background information. Now let’s get into the details of how you can protect yourself against viruses.

Antivirus protection

The most important form of protection is an antivirus. This is a software program that runs on your computer and constantly scans for viruses and potential threats. Having an up to date antivirus program on your computer reduces the chance of it becoming infected. Even if you download a malicious file, chances are a good antivirus program will block it.

There are lots of different antivirus providers including:

If you want to download and install a free antivirus the best one in our opinion is:

Are paid Antivirus programs better than free ones?

This is a very common question and often people will assume that paid antivirus programs are better than free ones. In truth, that is not always the case. Whilst paid programs do tend to have more features such as web protection and firewall utilities the free antivirus programs are very comprehensive and offer a very similar level of protection.

The main downside to free antivirus programs is that the provider will always try to “up-sell” the paid version to you. This often results in the free version having a time limit – for example, it may stop working after 12 months. If you are comfortable uninstalling and reinstalling programs then you can simply remove the old version once it stops working and then reinstalls the latest free version of the program. In our opinion, this offers sufficient protection. However, if you are not comfortable carrying out this type of task, then the paid antivirus providers offer constant protection and peace of mind without you having to do anything extra.

Keep your computer up to date

Once a hacker has downloaded their virus to your computer, it still has to work its way into your computer system. This is often done by taking advantage of weaknesses in the operating system. These weaknesses almost always come from out of date software. For this reason, it is extremely important to keep your computer up to date.

Regularly installing Windows updates as well as updating any other programs that you have installed on your computer is a great way to protect yourself against the most common viruses. This can make a real difference to your computer security and can help to protect your machine even if you accidentally download a virus AND it manages to get past your antivirus software. For this reason, updating your device is a crucial part of computer security.

Be vigilant when browsing the Internet and opening emails

Once your computer is fully protected and up to date, the last form of defence is your own vigilance. When you are browsing the internet this vigilance should come in the form of watching what sites you visit. As a general rule of thumb, you should avoid visiting any website unless you know who is behind it. For example, sites like Wikipedia or those owned by popular newspapers, such as the Daily Mail, are safe to visit. If you are searching on Google and come across a random website in the results, it is best not to visit that site – because you have no way of estimating whether or not that site is safe to visit.

If you have to visit a site that you have not heard of, you shouldn’t do so unless you have found it through a legitimate source – for example, if it’s been mentioned on the TV, or if you have seen it mentioned on a well-known website (Not including search engines). If you follow this rule and the following paragraph about email vigilance, then you would almost nullify any risk of picking up a computer virus.

Email security

As we mentioned previously, email is one of the most common ways a virus can get into your system. Hackers are very clever people and they will use all sorts of psychological tricks to try and convince you to open attachments or click on links in your email. This includes:

  • Designing an email to look like it has come from a legitimate company such as Royal Mail
  • Wording the email so it looks like it has been sent from someone that you know
  • Wording the email so it sounds urgent – in this case, the hacker is using a psychological trick to try and make you open the email before you even have time to consider whether or not it is legitimate

Keeping these points in mind when checking your emails can help you to spot, and avoid opening, any suspicious emails.

In addition to these pointers, a good rule of thumb is to treat every email as suspicious until you can prove otherwise. First of all, think about who the email is from – do you know this person or company? Even if you think you know then, next think about the subject of the email – does it relate specifically to something that you are expecting? Can you see any reference numbers in the email that you can match up via other sources to confirm it is genuine? If not then don’t open it.

Lastly, you can also look at the content of an email – you won’t get infected just by opening the email, rather you have to either click on a link or open an attachment for the virus to download itself. For this reason, any email with a link or an attachment is always far more likely to contain a virus and should be treated with even greater suspicion.

If the email contains a link you can hover your mouse over the link to reveal the true URL – if this does not match the URL text of the link itself then it’s probably a scam.

If an email contains an attachment you should be certain that you know specifically what the attachment relates to, and cross-reference the email with an external source – for example linking an order reference number with the email – before opening it.

Password security

Sometimes keeping your computer well protected isn’t enough. This is especially true when you have any type of online account. This invariably means that some of your personal data is held online.

The best form of protection for any information that you have online is your passwords. It is important to use very strong passwords for any services that you subscribe to including online banking and online shopping accounts. These accounts often contain sensitive information such as bank details, but even if they only contain personal details about you, they should be treated as precious because that information can be used by hackers in social engineering attacks.

A common form of attack used by hackers is to steal passwords from a large online provider – think of the recent British Airways hacking scandal – and then use the information gained from that attack to either compromise other devices and accounts belonging to the user, or use the information to compose targeted emails to the user in order to extort money from them (This has been a very common practice recently with hackers sending ransom emails and using personally identified data to trick the victim into thinking they have access to their devices).

Making sure you have passwords that are secure and have never been compromised is a great way of preventing this type of attack from being applicable. You can use this online service to check whether your password is secure – – if a password has ever been found on any databases from compromised websites, or on any lists being sold on the dark web this website will alert you to that fact. In this case, you should stop using that password immediately.

Two-factor authentication

Taking this a step further involves setting up two-factor authentication on your most sensitive online accounts. This typically involves the use of a text message or email that is sent every time you want to log in – that way it is only possible to access the account if you have the password AND access to the email or phone associated with the account. This form of authentication is available from the most popular online services and makes it extremely difficult for a hacker to compromise your account.


If you have any questions about the information provided in this article please comment below. We will try to provide replies to any questions asked.


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