to perform a legitimate act, such as maximizing a hard drive's efficiency, but actually performs a
destructive act. The "Jerusalem" virus was of this genre.
Part M: Infection Protection
"Aristotle said that the unexamined life is not worth living. We say the unexamined program is
not worth running."
PC Magazine
PCs are especially vulnerable to "software attack" because of the large amount of software
exchanged by users. There is no foolproof way of preventing an attack or detecting a destructive
program which gets into your software, but to help keep your software "infection free," you should:
Use only Army-provided software on your PC. Any software could contain one of these destructive
programs, but most Army-developed software and Army-provided commercial software is safe. If you
receive an original disk in a "shrink-wrap" package, it is probably not infected.
Use "public domain" software with caution! This software usually comes from computer clubs or
computer bulletin boards. Public domain software is not covered by copyright, and anyone can copy
it and use it, without restriction. This software is a leading source of infection, and unless it comes
from a known and trusted source, don't use it.
Don't use pirated software! Pirating software is illegal, and pirated software is a major breeding
ground for destructive programs.
Make frequent backup copies of your data disks. This will not prevent a software attack, but it will
help you recover from one.
Don't let a stranger use your PC. Make sure that only authorized persons use your PC, and make
sure that repair personnel perform only authorized repairs or modifications.
Finally, consider using one of the various "vaccine" program which are designed to detect viruses in
your software.
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