How many and which programs would give me maximum protection from computer virii?
(Let’s assume that we aren’t accounting for new virii that might be created tomorrow…what’s the state of the art today?)
ps. “Turn your computer off” is not a valid response 
Shesh I bet you’re ruling out “Unplug it from the internet” too. Some people are so darn picky.
In reality I doubt that more than two would add any real protection. The big anti-virus companies spend a lot of time keeping their signature files up to date with emerging virii.
Kaspersky seems to be the best, but it ain’t cheap.
The conventional wisdom is to not run more than one anti-virus program at once.
You can run more than one anti-malware program together.
Me: Microsoft Security Essentials, MalwareByte’s Anti-Malware, SuperAntiSpyware.
But the major threat is future viruses. Most anti-virus programs can detect existing viruses with a 95%+ hit rate by scanning for their signatures (see comparative tests like VB100 for a sample); it’s detecting and removing unknown viruses through heuristics and behavior analysis that’s difficult. Besides, there’s more to an antivirus program than how many it can detect; usability is another big one, and a common example is that people often choose to uninstall Norton’s products because they’re perceived as bloated and slow.
Besides, an anti-virus program is just one line of defense – even if it includes anti-spyware protection, rootkit protection, and a firewall. Before antivirus comes good overall security practices and after it comes OS-level security. An antivirus program by itself isn’t going to keep you safe; it’s like putting on a condom but then jumping into a swimming pool of ebola-tainted blood. You’ll need the whole hazmat suit to be safer, but more than that – stay away from the damned ebolapool to begin with!
That said, I use Avast myself, but only because it’s free.
Linux is pretty safe.
More important than your choice of antivirus is doing the following:
[ul]
[li]Running Windows 7 instead of XP (yeah, yeah, linux or snow leopard is safer, but I’m assuming we’re sticking with a MS product here).[/li][li]Stay current with Windows updates, as well as flash and adobe updates.[/li][li]Do not run in admin mode.[/li][li]Leave UAC on.[/li][li]Use Firefox or Chrome instead of Internet Explorer.[/li][li]Add noflash/adblock/nojava extensions, so that the only flash and java you run is the stuff that you intended to see.[/li][li]Don’t download torrents and other files from sites that you can’t trust.[/li][li]That goes double for pirated files.[/li][li]Don’t open emails if you don’t know the source. Don’t use a preview pane either, that’s the same as opening it[/li][/ul]If you do all those, antivirus is very nearly superfluous. I have had just one virus in the last decade plus, and it happened because I broke one of the rules above. I run MSE anyway (formerly McAfee until Comcast stopped supporting the free version) just to be safe, but it hasn’t been needed in yonks.
Pretty safe, but [=1&critical=2&impact=0&where=0"]not immune](About Secunia Research | Flexera[).
I don’t know if it’s any safer than a well-maintained Windows 7 installation, either, especially with a limited user account, UAC, and IE8’s Protected Mode (all on by default).
And JSexton, it’s not been shown (to my knowledge) that Firefox is safer than IE8 in Protected Mode. Firefox does tend to get patched quicker once an exploit is found, but IE may be more resistant to unknowns. Chrome uses a similar sandboxing model, but handles plugins differently – meaning it may be more vulnerable to Flash vulnerabilities than IE8 is. I’m not an expert in this realm, though, so feel free to correct me if I’m wrong… but if I’m not, I think Microsoft deserves some credit. They’ve come a long way since Windows XP and IE6.
ETA: If it’s any indication, at the last Pwn2Own hacking contest, FF, IE, and Safari were all broken (though it’s unclear whether IE’s sandbox mitigated the amount of damage done). Nobody tried with Chrome.
One program. Deep freeze
^ Vundo can beat that. It was the main security system at my local college, and they still kept getting Vundo infections. It turns out there’s a pretty well known exploit that could get access to the cloned copy without the password.
It’s been a few years, so I hope they’ve fixed it, but is sure wasn’t bullet-proof then.
Also, I recomend using HijackThis and something like Process Guard. One can tell you anything running on your system, the other will allow you to stop any executable from running. It just requires you to be vigilant about what programs actually belong to you.
Finally, in what way is Windows 7 more secure than XP with an LUA?
Hijackthis is of limited use these days. Viruses know how to hide from it.
What you generally need is one antivirus (Microsoft Security Essentials for a free one) and one spyware clearer (Malwarebytes of Super Antispyware).