Updating is normal and desirable
You should do a manual scan every now
and then. Scan every other week or so. Open the application, follow the
prompts which will guide you to perform a scan.
A-S applications - for non-viral malware.
The effectiveness of an individual A-S scanners can be wide-ranging and
oftentimes a collection of scanners is best. There isn't one software that
cleans and immunizes you against everything. That's why you need multiple
products to do the job i.e. overlap their coverage - one may catch what
another may miss, (grab'em all).
SuperAntispyware - Free
http://www.superantispyware.com/superantispywarefreevspro.html
and
Ad-Aware 2007 - Free
http://www.lavasoftusa.com/products/ad_aware_free.php
http://www.download.com/3000-2144-10045910.html
and
Spybot Search & Destroy - Free
http://www.safer-networking.org/en/download/index.html
and
Windows Defender - Free (build-in in Vista)
http://www.microsoft.com/athome/security/spyware/software/default.mspx
WD monitors the start-registry and hooks registers/files to prevent
spyware
and worms to install to the OS.
Interesting reading:
http://www.pcworld.com/article/id,136195/article.html
"...Windows Defender did excel in behavior-based protection, which detects
changes to key areas of the system without having to know anything about
the actual threat."
SpywareBlaster is not a scanner application.
It prevents the installation of ActiveX-based spyware, adware, browser
hijackers, dialers, and other potentially unwanted software.
Blocks spyware/tracking cookies in Internet Explorer and Mozilla Firefox.
Restricts the actions of potentially unwanted sites in Internet Explorer.
Keep it and keep it updated!
