Free Antivirus Software Legally protect your PC for free

Every computer connected to the internet is vulnerable to viruses, fraud and infiltration. This leaves our pockets prey to the software protection industry's heavy charges to keep us safe.

Yet it's possible to get legal, professional-quality antivirus and other protective software, absolutely free.

Always be careful to check any software you put on your computer is suitable and compatible with your existing set-up. No liability can be accepted for any individual problems caused by acting upon the information given.

Five simple ways to protect yourself

Getting software to protect your computer is unfortunately a must these days. Yet before you get there, you can take simple actions to up your protection without any new programs:

The banks say "if you don't have it, you could be liable"

If you're not protected and someone uses your computer to get passwords or access your bank account or other financial products, you may find it harder to get a refund.

The burden of proof's on the bank to demonstrate you didn't act with care, but it's best to be safe. For more on what to do if you think you've been defrauded read the ID Fraud Protection guide.

What are the main threats?

Threats to your computer come in different guises with various funky names. Collectively they're considered malicious software, abbreviated to "malware" in security parlance. The main types are:

1. 

   Viruses. Hidden programs that wreak havoc.

   These are transmitted via websites, email attachments, directly over the internet or via any other removable media. They hide in applications or files and spread from computer-to-computer, generally wreaking havoc wherever they get the chance to.

2. 

   Trojans. Bugs within harmless-looking files.

   Trojan (horses) are hidden within a harmless-looking file, eg, a picture of a celebrity, aiming to trick the user into installing the malicious software, eg, spyware or adware on the computer.

3. Worms. Can drill in via open web connections.

   Worms take advantage of any open internet connection, to try and sneak in and replicate on the computer. Once loaded, they often start to send spam email from your computer without your knowledge.

It's often about big, organised crime

It's a common misconception that producing computer viruses is the domain of angst-ridden web kids with little to do, showing off to their equally reclusive peers. While there may have been some truth in this at the beginning, and of course it still happens, these days it's often about big criminal business. Some of the reasons it happens include...

• Stealing your information

  Cracking into your computer can reveal a breadth of information about you, possibly including bank details for ID fraud or just directly taking your cash.

• Grabbing your email contacts

  It may be a program looking to grab all the emails in your address book/contacts list in order to find real addresses to sell to spammers. These people may well then be emailed from your address.

• Using your computer to threaten websites

  Some viruses allow your computer to be controlled in order to create a 'DDOS' attack, where a website is closed down due to simulated, simultaneous use by billions of users. This can be for political reasons, ransom, to hurt competitors or "just for fun".

  Many of the people whose computers cause this are unaware it's happening, as viruses are controlling their web connections. This site was hit by such an attack, where ironically some of the people denied access for three days could've been contributing to the closure via hidden viruses on their system.

Free antivirus software

Pay for antivirus software from biggies like Symantec/Norton or Kaspersky and it'll cost around £50 per year. Yet you can get free software which, while not quite as effective as paid-for programs, still keep on top of threats. Regardless of which route you take, heed the following:

Hackers develop new bugs constantly. All these free antivirus services offer regular updates, so make sure you get them!

Yet it's not just about how up-to-date your software is. If you're not using it, what's the point? Try to fit in a full "on-demand" scan (that is, one where the virus scanner flicks through all the files on your hard drive) once a week. This should make sure nothing slips through the net.

Firewall software - do you need it?

Antivirus software isn't the only protection your computer needs. If you don't have a firewall, you're leaving all your files and sensitive information vulnerable. Effectively:

Antivirus software = the border patrol checking what's allowed in

Firewall = the fence stopping it getting there in the first place.

So why aren't we all going firewall mad? That's because these days we tend to connect to the web via a router, rather than just a modem, and routers provide a hardware firewall. Ensure yours is switched on and set to a high enough security level. Consult the manual or search online for the make and model number if you don't know how to check.

While you're there, check your router password has been changed from its default; you'd be surprised at how many connections are hacked simply because the standard password hasn't been changed. Spend a little time to get your settings right here, as router firewalls give a higher level of protection than software ones.

If you don't connect via a router, or you're just big on your online security, here are the top freebies:

If you know or use any other free antivirus packages or firewall software, please share it in the forum discussion.

Adware and Spyware

There are two more commercial types of malware you can find on your computer. Often legitimate developers will design programs which incorporate useful functions, but unbeknown to you either provide them with information about you or try to sell you things. They fall into two main categories:

• 

  Adware. Pop-ups that try to sell you things

  Adware is malware that sneaks onto your machine and opens up pop-up windows that sell you things - often, but not exclusively, gambling sites.
  
  It's easy to assume these are related to the site you were visiting, yet often they aren't - its adware. If you've closed your browser but pop-up windows still appear on your desktop, chances are you've been infected.

• 

  Spyware. It tracks what you do
  
  Spyware is a more dangerous, less noticeable type of malware which covertly grabs information from your PC and sends it back to its leader out in the cyber-ether.
  
  Owing undoubtedly to their potential for criminal money-making, malicious spyware programs have become much more advanced in recent years, to the extent that some of the top spyware removers of yesterday can no longer cope.

Basic anti-adware/spyware measures:

To put your mind at rest you'll need to download some extra software, but in the meantime there are a couple of basic things to do:

• Use a pop-up blocker
  
  If you're being troubled by adware, use a pop-up blocker to alleviate the symptoms while you find a solution. Do be aware though, not all pop-ups are bad; some sites open new windows in this way - if you want to see them, hold down CTRL while clicking the link.

• Check whether you allowed the spyware

  There are a couple of legit spyware programs too; Google's Desktop (if you allow it to) can send info on what you've been searching back to Google, and Alexa's toolbar can do the same. In both cases the aim is to monitor your computer to help develop their products with data about people's searching habits.

  Whether you allow this depends on your view on how you want the information to be used. It's mostly harmless but does mean someone, somewhere has access to your searching habits.

• Be careful when downloading

  The usual way for ad/spyware programs to get on your computer is by attaching themselves to other things you download. So make sure you check the veracity of download sources before getting files.

• Delete programs you don't use

  Use the add/delete function on your Control Panel to get rid of any programs you don't need anymore; they may be corrupted.

Like most antivirus tools, spyware removers work by comparing what's on your machine to a list of known offenders. As ever, the top anti-ad/spyware programs are commercial, but that doesn't necessarily mean you need to buy them. Try these first:

Dodging spam emails

Want dodgy viagra or a fake watch? Want to invest in non-existent shares or visit fraudulent pornography sites? Or do you just want to click on a fake email from your bank to have your password stolen (read the full Phishing Scam guide)? You may think it unlikely anyone would say yes, but if that were true, criminals wouldn't bother sending out the emails.

For most of us, spam is time-consuming to wade through and potentially dangerous. Sadly, while you can register to stop junk mail or phone calls (see Junk the Junk guide) the same isn't true with spam email. Still, here are some dos and don'ts to keep the spammers at bay:

Spam dos and don'ts

Free back-up software

We've all had moments of horror (even in this very office) where due to hardware failure, power cuts or just plain ol' silly mistakes, precious documents disappear. As more and more of our lives are committed to the digital domain, backing up data is becoming more and more important, and since there are ways to do it free, you'll only have yourself to blame if you don't.

If your PC broke, what files would you miss most? These are the ones you should be backing up as a minimum.

Use hardware If you'd rather keep more tangible copies of your files, the options are either storing them on CDs and DVDs (you'll need a CD/DVD writer), or on an external USB hard drive for bigger/more files. As technology marches on, the latter are getting increasingly cheap; 1TB (1,000GB) for around £60 is now the norm if you buy online.

Use online storage This is a growing sector, and so as companies compete to gather custom there's loads of free space up for grabs. US site Adrive offers a mammoth 50GB free with its Basic package, making it the leader in terms of allowance, though Windows Live Skydrive (25GB) is also worth a look. There are a couple of downsides to using these; aside from the obvious worry about handing your data over to a third party, uploading's often painfully slow, and you'll have to log-in intermittently so they don't think you've disappeared and strike your files from their servers.

Software of the last resort: Recovery programs

If you've already lost valuable files, there may still be some hope in the form of recovery programs. Freeware programs Restoration, Freeundelete and PCInspector work to recover lost files, but as you may expect, it's a bit of a lottery as to whether they actually succeed.