PART 2 OF 2

     Last Blog I discussed what a virus is and how it multiplies.  I also discussed why viruses are written and how they effect our lives.  This column I will explain how to deal with viruses.

How can you tell when a program is infected with a virus?

     You can’t, at least not without the use of an anti-virus program, or knowledge of a specific virus.  An infected program can be disguised as anything from a game to a database management program.  Viruses cannot infect data files (with some exceptions), only executable program files.  Though data files can be corrupted by a virus, it would do no good for a virus to infect such a file.  This is due to the fact that a data file is never executed (in contrast to a program file), giving no chance for the virus to be started. By searching for specific combinations of codes, and comparing them to a virus information database, anti-virus programs can locate virus infected programs and disks.  Once located, procedures can be taken to remove the virus effectively.

How do I check if my computer system has any viruses?

(and if it does, how do I remove them?)

     Using an anti-virus program, most viruses can be found and safely eliminated.  Problems do exist though.  As new viruses are always being written, with the intention of deceiving current anti-virus programs; many new viruses are certain not to be found.  The best defense then, is simply to use the most recent update of a particular anti-virus program.  Many viruses simply attach themselves to the beginning of a program.  Once discovered, they can be eliminated by removing them from the program to which they are attached.  Some viruses actually overwrite part or all of a program.  This necessitates deleting the whole program, and restoring it from an uninfected backup.  Certain viruses will attach themselves to the ‘boot’ section of a disk (the section designed to tell the computer what to do when it is first powered on).  In this case, the ‘boot’ section can usually be replaced with an uninfected copy supplied with the anti-virus program.  Data encrypted by a virus can be unencrypted with the use of a specific anti-virus program, often by purposeful collaboration.  More destructive viruses that actually overwrite data with random information, or characteristic messages offer no means of retrieval.  Once these more destructive viruses are removed, the only way to restore lost data is via backups or from re-creation of the lost data.  To summarize, regular use of an up-to-date anti-virus program, and routine backups of valuable data, are the best defenses against viruses.

What steps can I take to avoid viruses?

     When receiving programs over the Internet and shared Thumbdrives, run an anti-virus program on the questioned program or Thumbdrive.  An anti-virus program running in the background can also help to catch a virus when activated; usually, before it has a chance to do any damage.

Will there ever be a definite cure against computer viruses?

     In short; no.  As long as programmers have ingenuity, and are presented with a challenge, new viruses will emerge.  Laws, anti-virus programs, government raids, and other deterrents will only increase the challenge and the thrill presented to the hacker.  But, fret not; anti-virus writers will continue to work (almost hand-in-hand) with virus writers to keep the computer world a virus free place.

A Lesson in Computer Viruses and how to deal with them (Part 1 of 2)