F5) How often should we upgrade our anti-virus tools to minimize
    software and labor costs and maximize our protection?

This is a difficult question to answer.  Antiviral software is a kind
of insurance, and these type of calculations are difficult.

There are two things to watch out for here: the general "style" of the
software, and the signatures which scanners use to identify viruses.
Scanners should be updated more frequently than other software, and it
is probably a good idea to update your set of signatures at least once
every two months.

Some antiviral software looks for changes to programs or specific
types of viral "activity," and these programs generally claim to be
good for "all current and future viral programs."  However, even these
programs cannot guarantee to protect against all future viruses, and
should probably be upgraded once per year.

Of course, not every anti-virus product is effective against all
viruses, even if upgraded regularly.  Thus, do *not* depend on the
fact that you have upgraded your product recently as a guarantee that
your system is free of viruses!



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