I've been using Avast! plus Defender. Is that redundant?
No, it's not redundant. They are two different things. Avast! is an
anti-virus program, but Defender is anti-spyware.
As a matter of fact, it's not even sufficient. A single anti-spyware
program such as Defender, no matter how good it is, is not good enough
to fully protect you. Note what Eric Howes, who has done extensive
testing on Anti-Spyware products, states:
"No single anti-spyware scanner removes everything. Even the
best-performing anti-spyware scanner in these tests missed fully one
quarter of the "critical" files and Registry entries" See
http://spywarewarrior.com/asw-test-guide.htm
So given that a single product is not enough for good protection, two
are better than one, three are better than two, and so on.
Do you "need" more than two? There's no clear answer to those
questions. My own practice is very conservative, and I
personally run
Spybot Search and Destroy
Adaware
Spyware Blaster
Windows Defender
Super-Antispyware
A-Squared
but not at the same time.
I *never* visit risky sites or open questionable email
attachments, etc.
Taking such care is a very good thing to do, but there are two
problems:
1. Although there are some web sites that are clearly risky to visit,
with others it isn't so clear, and it's very hard to sure that you
don't make a mistake. That's why it's good to add anti-spyware and
anti-virus software to your protection, and not *just* rely on staying
away from risky sites.
2. Similarly, it's very hard to know in advance which E-mail
attachments are questionable. You often see advice not to open
attachments from people you don't know. I think that that's one of the
most dangerous pieces of advice you see around, because it implies
that it's safe to do the opposite--open attachments from friends and
relatives. But many viruses spread by sending themselves to everyone
in the infected party's address book, so attachments received from
friends are perhaps the *most* risky to open.
Even if the attachment legitimately comes from a friend, it can
contain a virus. I'm not suggesting that a friend is likely to send
you a virus on purpose, but if the friend is infected without
realizing it, any attachment he sends you is likely to also be
infected.
Personally I never open executable attachments at all, except from a
*very* few trusted sources, and then only when I'm expecting them.
