If you suspect that your PC has been infected by malware (virus, Trojan, adware, spyware, etc.), one of your first stops should be at a web site that allows you to download a free antivirus package.
Many companies offer free programs that are cut-down versions of their commercial products. Some programs are also available as freeware or Open Source. In general, these antivirus programs are free for non-commercial use only. This means that the program can only be used at home or college and is for your personal use only. If you use the program at work, or install it on more than one computer system at a time, you are usually required to pay for it.
Some companies ask you to register the software before using it. Registration is often required if you want to be able to update the program via the Internet. Although it might be a little inconvenient, registration costs nothing and helps software developers continue to let people use their programs for free.
Although antivirus programs may offer lots of different features, most work in basically the same way. When the program first starts, there is a short delay while it checks the computer's memory and other locations for signs of virus infection. Next, the program will usually attempt to update its internal database of virus information via the Internet. The amount of time this takes will vary according to the speed of your Internet connection but shouldn't take more than a minute of two. Once any updates have been downloaded, the program will then carry out a full scan of your machine. This can take a long time, so be prepared to wait patiently or, better still, go and grab a coffee!
