Free Anti Virus, Firewall, Trojan, Spyware AdviceFeaturedPopular
The most common blunder people make when the topic of a computer virus arises is to refer to a worm or Trojan horse as a virus. While the words Trojan, worm and virus are often used interchangeably, they are not the same. Viruses, worms and Trojan Horses are all malicious programs that can cause damage to your computer, but there are differences among the three, and knowing those differences can help you to better protect your computer from their often damaging effects.
A computer virus attaches itself to a program or file so it can spread from one computer to another, leaving infections as it travels. Computer viruses can range in severity: Some viruses cause only mildly annoying effects while others can damage your hardware, software or files. Almost all viruses are attached to an executable file, which means the virus may exist on your computer but it cannot infect your computer unless you run or open the malicious program
A worm is similar to a virus by its design, and is considered to be a sub-class of a virus. Worms spread from computer to computer, but unlike a virus, it has the capability to travel without any help from a person. A worm takes advantage of file or information transport features on your system, which allows it to travel unaided. The biggest danger with a worm is its capability to replicate itself on your system, so rather than your computer sending out a single worm, it could send out hundreds or thousands of copies of itself, creating a huge devastating effect. One example would be for a worm to send a copy of itself to everyone listed in your e-mail address book.
A Trojan Horse is full of as much trickery as the mythological Trojan Horse it was named after. The Trojan Horse, at first glance will appear to be useful software but will actually do damage once installed or run on your computer. Those on the receiving end of a Trojan Horse are usually tricked into opening them because they appear to be receiving legitimate software or files from a legitimate source. When a Trojan is activated on your computer, the results can vary. Some Trojans are designed to be more annoying than malicious (like changing your desktop, adding silly active desktop icons) or they can cause serious damage by deleting files and destroying information on your system. Trojans are also known to create a backdoor on your computer that gives malicious users access to your system, possibly allowing confidential or personal information to be compromised. Unlike viruses and worms, Trojans do not reproduce by infecting other files nor do they self-replicate.
Adware or advertising-supported software is any software package which automatically plays, displays, or downloads advertising material to a computer after the software is installed on it or while the application is being used. The more adware packages installed on your pc the slower your internet connection becomes thus a good adware remover is needed to keep your pc adware free.
Combating Viruses, Worms and Trojan Horses & Adware
The first steps to protecting your computer are to ensure your operating system (OS) is up-to-date. This is essential if you are running a Microsoft Windows OS. Secondly, you should have anti-virus, adware and anti trojan software installed on your system and ensure you download updates frequently to ensure your software has the latest fixes for new viruses, worms, and Trojan horses. Additionally, you want to make sure your anti-virus program has the capability to scan e-mail and files as they are downloaded from the Internet. This will help prevent malicious programs from even reaching your computer. You should also install a firewall as well.
There are a lot of good freeware utilities out there but the deference between the full and the free versions is that the free version has certain features disabled and may not automatically update. The auto update is probably the biggest problem where the average user forgets to regularly update the antivirus, adware etc software. Buying the full auto version of the software is a small price to pay to have your PC fully protected.
The list below features my personal pick of the best PC security utilities.
Anti-Virus Software First there is Norton Antivirus 2007 which is an industrial strength AV which blocks viruses and spyware with advanced protection.
Equally effective is CA Anti-Virus 2007 which provides complete protection against viruses, worms and Trojan horse programs.
Spyware has evolved so quickly that some AV products are no longer up to the task of providing primary protection from Adware/Spyware and Scumware. I suggest to install a dedicate spyware scanner in combination with your antivirus products.
My first choice is Ad-Aware from Lavasoft and is a flagship product. Ad-Aware is a multi-component detection and removal utility.
My second choice is spyware detector. The software is specially designed to scan, detect, delete and recover spyware with an option of quick and full scan.
No other single product class seems to cause as much trouble to average users in their installation and day-to-day use as Firewalls. For such users, Sunbelt Kerio Personal Firewall is my top recommendation.
If performance rather than ease-of-use is your criterion then the Comodo firewall is the top contender. The firewall itself is very robust and it comes with a well designed intrusion detection system as well.
Trojan Scanner/Trojan Remover My top recommendation here is Trojan Hunter it is an industrial strength trojan remover and is the only scanner capable of cleaning process-injecting trojans.
My second recommendation here is Ewido which is now called AVG Anti-Spyware.
My Third recommendation is a2 (a-squared) anti-trojan as an alternative.
Note: The free version of AVG Anti-Spyware is actually the same as the paid version but after 30 days the active protection (i.e. memory monitor) becomes non-functional, automatic updates are disabled and kernel level self protection is turned off.
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The most common blunder people make when the topic of a computer virus arises is to refer to a worm or Trojan horse as a virus. While the words Trojan, worm and virus are often used interchangeably, they are not the same. Viruses, worms and Trojan Horses are all malicious programs that can cause damage to your computer, but there are differences among the three, and knowing those differences can help you to better protect your computer from their often damaging effects. 
