Computer Viruses constitute one of the most common and high profile threats to Personal Computers and Computer Networks, yet awareness of computer viruses is often poor; i.e. what is a virus and how do they infect a PC.

While there is no widely accepted definitions of the terms "Computer Virus" and "worm", the following loose definitions should suffice:

• A computer virus is executable code that, when run on a computer, attaches itself to other executable code, in memory or on the hard drive, in an effort to reproduce itself. Some computer viruses are malicious; erasing files, locking up systems, or sending mass e-mails while others merely present a problem solely through the act of infecting other code.
• A Worm is a self-propagating virus.
   

Closely related to computer viruses are Trojan Horses.

A Trojan Horse is a program that performs some undesired yet intended action while pretending to do something else. A Trojan Horse application is a malicious program that is disguised as something benign.
 

• Once unleashed, a Trojan Horse performs far different tasks than you would expect, such as sending itself to everyone in your email address book, erasing your files, or stealing your passwords.
• Games, utilities, or intriguing message attachments are just some examples of how a Trojan Horse might disguise itself to fool a user.
• One common class of Trojans are fake login programs - collecting account usernames and passwords by prompting for this info just like a normal login program does then sending the information to the program author.
• Another common Trojan is a disk defragmenter that erases files rather than reorganizing them.
• Some more advanced Trojan Horse applications, called "active" Trojan Horses, can even allow a hacker to take control of your computer.
• Active Trojan Horse applications are known to use an unprotected port on the infected computer to communicate.
• Active Trojan Horses are also commonly called Remote Access Trojans.
• A Trojan Horse differs from a virus in that a Trojan Horse program does not attempt to reproduce itself.

Viruses come in many shapes and sizes, such as:

• File infectors
• Cluster infectors
• Macro viruses
• System infectors

A virus must be executed by someone, perhaps unwittingly, in order to spread. Some ways in which this occurs include:

• Booting from an infected floppy
• Running an infected program
• Opening an e-mail message with an attached virus
   

There are several methods of protecting your computer systems against attack by viruses. These include:

• Firewall based Anti-Virus
• Server based Anti-Virus
• PC based Anti-Virus

MicroServe also provides Anti-Virus and Anti-SpyWare as part of our Managed Security Service.  Click here for more details.

Some other aspects of Network Security include:

• Firewalls
• Virtual Private Networks (VPN)
• Managed Security Services

There are many different solutions available to protect your computer systems against virus attack.  Call us toll free at (866) 382-8009 or locally at (240) 686-2012 to talk to one of our security consultants so we can help you determine what is the best method and product for your individual requirements. Our experts can help you select the solution, install the application and/or hardware, and configure it to provide maximum protection.