What Is
a Virus?
What Is a Virus Capable of Doing?
How Do I Protect a Computer From Viruses?
Virus Prevention Strategy
Common Signs of a Virus Infection
Methods to Limit Virus Infections
Summary
What
Is a Virus?
Many people realize the possibilities of what a virus can do to their system
and data, but they rarely understand what a virus is. Knowing what a virus
is, what it is capable of and what it's limitations are will put you in a
better position to deal with a virus infection should you ever have one.
Viruses are programs.
That's all they are. They are not magic, they're mystical and they're not
even difficult to create.
Once a virus program is created, it can be run to infect disks and programs.
When a virus infects a disk or program it can do a number of things, but the
one common goal of a virus is to spread.
A virus infects programs and disks by copying itself where it can be executed.
When infecting a program, the virus attaches itself to the file in such a
way that when the program is run, the virus can be executed too. In essence,
the virus is an addition to your regular program.
A special type of virus called the boot sector virus can attach itself to
a disk (hard drive or floppy) so that whenever the computer tries to boot
from the infected disk, the virus will be one of the first things to be run.
To understand this type of virus you have to understand the PC boot process.
When a PC is booted, it looks for a start-up program in what is called the
boot sector of the disk. A virus can pretend to be the start-up program by
putting itself in the boot sector of the disk.
Many viruses like to remain in memory as a TSR (Terminate and Stay Resident).
That way they can act out their functions whenever the computer is booted
from a boot sector virus or a infected program is executed.
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What
Is a Virus Capable of Doing?
Replicating itself to other programs and disks
Deleting files Corrupting files Formatting disks
Sending messages to the screen
Playing music
Slowing down the computer
Anything that a regular program could possibly do
How Does a Virus Get Into My System? Remember a virus is a program, you have
to execute the virus there are only two ways a virus gets executed. Either
by booting your computer with a disk infected with a boot sector virus or
by running a program infected with a virus.
That's it!
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How
Do I Protect a Computer From Viruses?
Make sure your data is backed up regularly
Use a virus detection utility on a regular basis and keep the virus detection
utilities up to date
Write protect disks when possible
Don't trust untested programs from anyone or any company
Have a write-protected emergency boot disk available
Have a write-protected emergency virus detection/removal utility disk available
Know who to contact for help
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Virus
Prevention Strategy
Fighting viruses can be like trying to put out those trick candles on your
birthday cake. Just when you think you've gotten rid of the last one, it comes
back again. For network administrators and security personnel, viruses are
one of the biggest nuisances to control.
For virus prevention to work, network users must exercise safe computing practices.
Network administration may take precautions by implementing virus detection
and removal utilities, but no system is foolproof. New viruses are created
all the time and current safeguards are not 100% impenetrable.
Conscious users can help stop the spread of computer viruses by taking precautions,
utilizing the virus utilities available and by knowing who to contact for
assistance.
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Common
Signs of a Virus Infection
Disk activity when there should not be any activity.
Some disk caches cause this to happen normally.
Programs that take longer to load but the disk drive appears to be healthy.
Any unexplained behavior on the PC such as music, bouncing balls, black areas
on the screen, falling letters, weird messages or an unexplained slowdown
of the PC.
Less total free (available) memory on your PC.
This should change only when you add new resident programs or device drivers.
Unexplained bad spots on your disk or fewer total bytes of free space.
If you find extra executable files showing up on your drive, you may have
a companion style virus.
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Methods
to Limit Virus Infections
Scan any new disks that are used on your system.
Do not trust any new software whether it is obtained from an individual, the
Internet or a company.
Enable the write protect tab on all your disks if possible.
If you find a virus, notify all users who have access to your system, disks
or software.
If you find a virus, check any removable disks that have been used in your
system, blank ones to
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Summary
There are too many myths about viruses that cause a typical user to panic
at the very sound of the word. Realizing that a virus is nothing more than
a program will help you sort out the fact from the fiction. Spread the word
when you find a virus. Chances are good that you're not the only one to have
the virus on your system.
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