The answers to that is… No, it does not. Site Advisor does, but McAfee as in a security program, it barely does its best. I had a virus and McAfee said I didn’t have one, and that’s not true, so that kind of made me switch to Norton, which works great, by the way.
I would recommend AVG, lighter, effective and free!
Yeah. AVG is great if you’re looking for a FREE Virus protection. Norton costs money, but IMO it works the best.
I have friends who I help out sometimes, by cleaning out all the viruses and spyware thier computers accumulate over time. My experience has been that every anti virus or spyware removal software I’ve tried, at least once, failed to detect something bad while another program picked it up.
My conclusion is that there is no single program which can always find everything. Obviously some are probably better than others.
This argument was made in countless threads over many sites. I am restating the general consensus, neither Norton nor McAfee are top players anymore. AVG provides average protection and more can not be expected from a free solution. As far as system resources required, true and false hits, currently the top choice is ESET NOD32. I personally use it and would recommend it.
I have actually tested this as well before. However, my results came back different than yours.
I prefer NORTON or AVG…I haven’t tried McAfee ever
i never want to use again McAfee…
i have same problem with vertical said. I have virus but after McAfee scan its nothing.
But after i move to AVG…its many virus…
I used AVG for a year and it never picked up a single peice of malware (or possibly one or two). That was particularly suspicious. I’m using Avira now and it picks up some, here and there, but it also tends to have some false positives (and unnecessary detection of EXE packers and such).
According to AV-Comparatives, NOD32 is the best. I don’t use it because I don’t really need anti-malware protection.
I personally stay away from any paid AV software. I’ve been using Avast! on my home PC for years and haven’t looked back once. It’s fast, does boot-time scanning, updates regularly. I’ve used AVG but didn’t like how limited it was.
top players:
NOD32
Avira
AVG
Avast
in no particular order
notice how most of them start with an A 
norton is the fastest and most pc demanding of them all, but i have a specific personal list of anti-viruses that people with viruses use.
order of severity: 1 extremely common, 2 common, 3 rare
1 kaspersky
1 Norton
1 McAfee
2 Panda
3 Avg
3 Nod32
i have fixed about a hundret pc’s over the last 8 years, and those antiviruses are the only ones i meet on BADLY infected pc’s
i personally use AVG, although i fancy avira as it seems to be the best one yet.
lets say the average client wants a pc that never (almost) gets any viruses, also he wants to experience a calm usage, and so that the antivirus stays “invisible” while doing what it does.
so that the user can experience the full potential of the pc without any additional headaches or viruses.
my likes/dislikes:
dislikes: norton is amazingly badly made, bugs every you for every little thing, takes ages to scan, blocks normal user activity, slows down the pc, and makes life as miserable as possible, as if i want to own a pc just for the sake of keeping viruses out and nothing more.
likes: finds all viruses. (if you have paid the $$$)
nod32: i don’t like the interface.
mcafee: no so good against viruses
kaspersky: annoyance not as bad as norton, but also has lower degree of real threats found.
Panda: not recommended, why pay so much for so little.
conclusion:
in real life you don’t even need a antivirus to stay safe from viruses, but its there, and its there to help, not annoy, and not to suck money away from your pockets.
the free ones are just as good as the paid ones in terms of virus protections, everything else can be solved using common sence.
like:
do not download fun.exe from suspicious sites
do not download any .exe from suspitios sites (if you don’t know what this is then enable your extensions)
enabling them:
vista: http://www.gilsmethod.com/how-to-display-file-extensions-in-vista
xp: http://www.windowsreference.com/windows-xp/how-to-view-all-file-extensions-in-windows-xp/
do not open spam mail, and so forth.
doing some of the above can and will infect ANY pc with any antivirus (if the virus is new enough)
so why should YOU pay for something you don’t need.
and why should it hider your everyday activities?
get avira, or avg, or nod32
get ad-aware or spybot search and destroy.
and a registry cleaner, like ccleaner
and type msconfig in start>run (or ccleaner) to remove as many autostart programs as possible (including some viruses and malware) only keep the necessary
note: all of above is free for personal use
and what do you get?
you get a close to free-of-viruses lifetime for free, much better than just one program!
this is just personal experience
until its time runs out, and your left unprotected without warning.
my opinion: do you really need another headache to worry about?
Yes, but you can purchase a 2 years license and you will not have problems for 2 years with your PC.
AVG for me 
I agree with YuriKolovsky, And I am a proud user of Avira (and have been for over 3 years) and it is less resource intensive, bulky, bloated and swollen than that evil minion Norton. As for McAfee why anyone would consider using that weak product for any form of protection is beyond me.
AVG works great.
I’ve used AVG for years now and it’s saved my nuts several times. I do use it in conjunction with ThreatFire, which got me out of a pretty nasty rootkit situation once.
Norton is just bloatware that gets uninstalled from wherever I find it!
I would suggest you switch to Avast Home Edition. It’s free and works really well. It detects both malwares and trojans from emails and browsers.
norton ALL THE WAY , especially since they made it lighter on sustem resources, money well spent
the best protection from viruses is by far common sense.
be careful with .exe files, don’t download from suspicious sites.
some computer specialists don’t even use a antivirus because in their opinion they are useless and take away pc resources.
so if your gona go for a antivirus, go with a free one, or use one that is good as a free version but buy the full version if your so eager to spend some money.
none of the antiviruses above offer you any protection if you happen to manually download a unknown virus.
a handy non antivirus solution to the virus problem would be to use sandboxie to open suspicious .exe files and check if they are viruses, and to use [URL=“http://www.acronis.com/”]acronis true image to backup your pc and restore it in case you catch a virus of some sort.
sources: been fixing pc’s with viruses (that had either kaspersky or norton or mcafee or panda installed) for years.