A virus is a malicious piece of software designed to cause your computer harm by removing or corrupting files. There are other types of software like ‘Malware’ and ‘spyware’ which are designed to harvest information from or allow access to your machine.
The best way to prevent infection is to install antivirus and firewall software. Once installed, it is important to regularly update them, as they will constantly protect your computer from threats. Should your computer become infected with a virus, a complete scan of your computer should locate and remove it for you.
If, even after a complete virus scan, you think the virus is still wreaking havoc with your computer, it would be a good idea to have your computer looked at by a local IT technician
A free online scan from somewhere like the Trend Micro home page, is recommended as a second opinion or if you suspect your own security software may be compromised: http://housecall.trendmicro.com
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