Posted 25 January 2009 - 08:23 AM
Especially with adware and spyware, since each company has a slightly different set of criteria its application looks for, having more than one is a good idea; often one will catch what another doesn't. At some stage, however, the situation becomes one of diminishing returns, and too many anti-spyware applications only serve to glug up your hard drive.
Moreover, there is another meaning for layered protection that suggests that having a resident AV with real-time protection), firewall, and anti-spyware applications, using a safer browser, and being cautious about downloading and surfing is computer security best practice.
Whereof one cannot speak, thereof one should be silent.