Virus Protection

 

Covering your mouth when you cough, blowing your nose into a handkerchief or washing your hands are things we all do daily in a subconscious effort to protect ourselves from illness.  If people thought about their computers with the same common sense we use when thinking about our own cleanliness, many of the problems computer users face on a daily basis could be eliminated or at least greatly reduced.  Viruses can cause you to loose important data, corrupt your file system, annoy friends and co workers that are in your contact list, and in some cases can require you to completely reformat your hard drive and start over.  Computer viruses are called viruses because they share similar traits to biological viruses like the flu and colds. A computer virus is specifically designed to damage your computer, files and data.  

 

Types of Computer Viruses

 

File Viruses

 

This is the most common form of virus.  They usually infect .exe and .com files which are the main executable files which make your programs run.  A file virus inserts its code into these .exe and .com files and start spreading as soon as you run the program.  Most file viruses are memory resident, meaning they stay active as long as the computer is left on, and each time you start another program it becomes infected as well.  Restarting the computer will usually stop the infection but will not fix files that are already corrupted, and running a previously infected program will start the whole process over again.  In the simplest file viruses the virus code will overwrite the program or applications .exe files causing the program not to run.  More complex file viruses can cause more damage, spread easier and can be a lot harder to detect.

 

Boot Sector/Partition Viruses

 

Boot sector viruses infect your hard drives or floppy drives boot sector.  The boot sector is the very first section of data on your drive and the part that allows the computer to boot properly.  Since they are written to the boot sector, they take control before the operating system even starts.  Since the code in Boot Sector viruses are not platform specific they can infect any PC operating system.  Once booted these viruses stay in ram and can infect any writable media read by the computer including floppy disks and cd-r/cd-rw.  These viruses are only spread through contact with an infected floppy disk or cd-rom.

 

Multi-Part Viruses

 

Multi-Part viruses combine the worst of file and boot partition viruses.  They spread like file viruses but write themselves to the boot sector, partition tables and program files, they can be very hard to remove.  They are transmitted my infected programs or booting from disks or drives that have been infected.

 

Macro Viruses

 

Macro Viruses consist of macros written for a specific application such as Word, Dbase, Excel or Access.  Macro viruses are usually found stored within a template or object of an office document.  Once they have been delivered they can corrupt other files of the same type and are generally platform independent.

 

Trojan Horses

 

A Trojan Horse is a computer program they usually claims to do one thing, for instance a game, but instead does something damaging to your computer.  Trojan Horses can open and take advantage of exploits in your computer operating system and in some cases give the person responsible for the Trojan complete and total control over your computer.  The good news is that Trojan Horses generally have no way to replicate automatically and can usually be detected and removed with no harm to the computer system.  SubSeven and Backorifice are two of the most common Trojan Horses.

 

Worms

 

A worm is a virus that uses computer networks such as the internet or an office environment to replicate itself.  It usually exploits common or not so common security holes to gain access to a computer.  Once a computer is infected with a worm, the worm then scans any networks the computer is attached to looking for other computers with the same security hole.  Once it finds a new machine to infect the process starts over.  Worms are responsible for a majority of the outside traffic discovered my personal firewalls.  Since the explosion on popularity of the Internet, worms have become the most prevalent form of virus found on computers today.  Because of a worms ability to copy itself from system to system, a single infection can spread incredibly fast.  For example in 2001 a worm was released called Code Red which replicated itself over 250,000 times in less than 9 hours.

 

Polymorphic Viruses

 

Most viruses found today are polymorphic in nature meaning that they can change their code yet remain fully operational.  The idea behind this is that by changing its signature it can be all but impossible to detect with anything but the latest virus scanners.

 

How to Protect Your Computer from Virus Infection

 

First off, if you don’t have an anti-virus program, get one.  You know the old saying an ounce of prevention is worth a pound of cure?  The hassle of even one virus infection will prove the value of a decent anti-virus program.

 

There are many choices for anti-virus protection.  A few of the recommended ones are:

 

 

McAfee Virus Scan

Company Web Site: http://www.mcaffee.com/

 

McAfee's is one of the oldest and most trusted anti-virus developers.  Their program includes both background (always-on) scanning and on demand scanning, as well as boot up utilities to help in disinfecting computers you suspect of being exposed to viruses.  Trial versions of their product can be found here.

 

McAfee also offers an online scanner which is no replacement for virus protection, but can help when you forget that ounce of prevention; you can find it at http://www.mcafee.com/myapps/mfs/default.asp

 

 

Norton Anti Virus

Company Website: http://www.norton.com/

 

Norton is probably the most recognized and respected name in the anti-virus business.  Their suite of anti-virus utilities includes both background and on demand scanning as well as boot utilities.

 

Norton offers trial versions of their most popular utilities here.

 

 

Panda Global Virus Insurance

Company Website: http://www.pandasoftware.com/

 

Panda is a relative newcomer to the anti-virus business but they offer a unique product that helps protect against system vulnerabilities as well as viruses.  Trial versions of their anti-virus suite can be found here.

 

Panda also offers a free online virus scanner at http://www.pandasoftware.com/activescan/com/activescan_principal.htm

 

 

PC-cillin

Company Website: http://www.trendmicro.com/en/home/us/personal.htm

 

PC-cillin is the flagship product of TrendMicro.  They have a fantastic virus response team and have been very successful and finding and eradicating viruses in the wild before they have become big problems.  Trail versions of their software can be found here.

 

TrendMicro, the makers of PC-cillin were the first to offer a free online scanner, you can find it at http://housecall.trendmicro.com/

 

 

Vexira Anti-Virus

Company Website: http://www.centralcommand.com/index.html

 

Vexira is another relative newcomer, but offers some unique features like script protection and P2P network protection.  They are multiplatform and trial versions of their software can be found here.

 

 

Beyond running anti-virus software there are a few basic rules to follow that can help prevent a virus from infecting you and those you care about.

 

1.      Never open an attachment from someone you do not know.  Friends, Family and Co-Workers that are uneducated about viruses can spread them without knowing, so if you receive an attachment from someone you do know, it is still a good idea to save it to disk before viewing so that the anti-virus software can safely scan it.

 

2.      Make sure that Macro Virus Protection is always turned on when you use programs such as Word, Excel and Access.  Never allow macros to run unless you are sure what they will do.  The ability to turn on and off Macro Virus Protection can usually be found under the tools/options dialogue box.

 

3.      Never forward virus alerts without a little research often these “alerts” turn out to be hoaxes and tend to cause as much problems by creating panic as real viruses.

 

4.      Run your anti-virus software often and keep it updated. All anti-virus programs offer free updates to keep you protected from the latest viruses. Not updating your anti-virus software makes the anti-virus protection worthless. Most anti-virus programs will let you schedule them to run automatically at any time you choose, late at night or any time when you are most likely to not be using the computer is a good time.

 

5.      Educate your friends, family and co-workers. Ask them what anti-virus program they use. If they tell you they don’t, take a minute and explain why it's important.

 

Following these basic steps can keep your computer running happy and virus-free.