Computer Virus Protection

Protecting yourself against viruses is a three step process.

1. Understanding the problem
2. Prevention and Protection
3. Decontamination of infected files/computers

Understanding the problem

Firstly, you need to be aware of what viruses are and how they work. There are many sites on the Internet that provide detailed information on computer viruses. Briefly though, the majority of viruses infect computers through emails (usually in attachments) or files downloaded from the Internet. There are an incredible number of viruses out there, and more are being recognised each day. They vary from 'harmless pranks' that write a message on your computer screen to programs that crash your entire computer to programs that allow other people (known as hackers) to gain access to anything that is stored on your hard drive. Even the smallest virus can be a major irritation though, so it's important to know how to recognise them and what to do when you think you have an infected email, file or computer.

Protection and Prevention

The most important step is to make sure that you have adequate virus protection, but there are other things that you can do to keep your computer virus-free. Protection and Prevention is a three-step process in itself.

Since most viruses arrive in the form of infected emails, your first line of defense is actually not up to you, but to your email server. Email services, including those offered by most Internet Service Providers, usually have some kind of virus filter protection for emails that are sent or received through them. Most ISPs keep their clients informed as to what kind of anti-virus measures they have in place, however if you are unsure, check with them to make certain that your emails are being filtered for viruses.

It's important to note that even the best anti-virus email filter won't pick up all viruses. There are so many of them that the filters can't possibly detect them all, and there's always a delay between when a new virus is created to when it can be successfully recognised and dealt with by email filters. So, your second line of defense is to have a good virus protection program installed on your computer, and make sure that the virus definitions that it uses are kept up-to-date! With several new viruses appearing every day, it's no use having an anti-virus program that doesn't protect against the latest threats to your computer.

There are several programs on the market, but the two most common ones are produced by Symantec (Norton's Anti-Virus) and McAffee. When your shopping for a virus protection program, make sure that you get one that offers frequent virus definition updates, since virus definitions are what the programs use to determine if a file or email is infected or not. Most virus protection programs are on a subscription basis and need to be renewed every year. This is due to the intense ongoing support (virus definition updates) given to these sorts of programs.

Make sure that your virus protection program is set to scan your incoming mail and notify you of any infection it finds. It's also good practice to scan your entire computer system on a regular basis, just in case.

Even with your email server and virus protection program working to help you keep your computer virus-free, filters and anti-virus programs are only as good as their virus definitions, so there's always the chance that an infected email could still get through. So, your third line of defense is to know what to look for in the emails that arrive in your mailbox, in case they're infected.

The best way to protect your computer is to treat every email that arrives as though it could be infected with a virus. There are three things that you need to look for.

1. Is the email from a recognised source? (an email address that you recognise, like a friend's or a company's that you often receive email from)
    
   If you don't recognise the source of the email, it could be a virus (or spam - which is almost as annoying). Keep in mind though that some viruses can draw email addresses from address books and mail themselves out, so a recognisable source is no assurance that it isn't an infected email. It just makes it less likely.
    
   
2. Does the email have a subject line that you recognise? (a response to an email that you sent out, a particular subject line that you recognise from coming from a certain website or email link, or something specific to you or your company)
    
   This is the hardest one to recognise. Most virus-infected emails have subject lines that seem harmless, like 'hi', 'hello', 'error', 'return to sender', 'message delivery failed' or many others. If you answered 'yes' to the previous question, then there's less of a chance that it could be infected, even if you don't recognise the subject line, but you should still be careful. If there's no subject line at all, don't open the email unless you can confirm what it contains! If the email is from a recognised source, and you have any doubt about the subject line, it never hurts to contact the source to double-check!
    
   
3. Does the email have a file attached? (viruses often hide in attachments)
    
   If there's an attachment and you've answered 'yes' to one or both of the previous questions, use your own judgement about whether or not to open the email. You're the only one who can determine how safe or risky it is, based on your knowledge of the source and subject. If you answered 'no' to both of them, there's a very good chance that it could be a virus, or spam. Either way, your best option is to delete it. If there is no attachment, it could still be a virus, so again use your own judgement about whether or not to open it.

Most viruses require you to actively open the email that contains them before they can activate, so your best method of prevention is not to open any email until you're sure that it's safe to do so. A little prevention will often save you a lot of time and trouble.

Decontamination of Infected Files/Computers

If you suspect that your computer has been infected by a virus, and you have a virus protection program, immediately run a full scan of your computer. If you don't have a virus protection program, you can either get one and then run a full scan of your computer, or there are websites that provide free virus scanning. Make sure you find a reputable site though and fair warning, those kinds of scans usually take an extremely long time.

If it's confirmed that you have a virus, generally virus protection programs will advise you on what course of action is required. Sometimes, deletion of the infected file is enough, but it depends on the virus. Some of the really bad ones require you to download a special file from the Internet (think of it as 'medicine' for your computer) to remove the virus completely. Others may be severe enough to require professional assistance. If you're at all unsure of what course of action to take, seek professional advice. If you know the name of the virus, sometimes looking it up on the Internet (search engine) will help too.

Keeping your computer safe from viruses doesn't just help you or your company. Because most viruses can be transmitted from one computer to another via email, proper virus protection on your part helps protect everyone that you send email to.

As computer viruses become more complex and more dangerous, prevention and protection becomes more important than ever.

Here are a couple of links that will help you to keep your computer safe.

Symantec - the makers of Norton's Anti-Virus (among other programs)

McAffee - the makers of numerous virus protection programs

Both of these sites contain huge knowledge bases with details on every known virus, an online virus scanning program and security check, information about viruses and spam and many other things. You can also find details about all of their virus-related programs.