I found out that AVG Free version isn't eliminating even trojan viruses. I only have this free version from protecting my system. Is it okay to install one more anti-virus software on top of this AVG Free version which is already installed and updated to the latest version?

I have the option of installing Norton Anti-virus 2005. Will it cause any problem since the two softwares may use the same source from the computer, if I install this one?

Do you recommend that I should uninstall first the existing software and install the new one?

Will Norton Anti-virus 2005 be more effective than AVG Free version (latest)?

I would be very happy to consider your feedbacks and recommendations. Thanks.

If you're running a Microsoft operating system, Microsft recommends that you only have one anti-virus installed.

I use Norton and am really happy with. Of course, it's important to keep the DAT files up-to-date to make sure that you're protected regardless of which anti-virus you use.

Do just like the lady says... One at a time and she prefers Norton.
I don't know that there is a single program that will catch everything.
The best approach is a proactive one.
Secure your machine with anti-virus and a firewall. (hardware via a router and software, also)
Also, consider that in case something does get in to your system, have the neccesary disks available to restore critical software and data.
No system is bullet proof, but taking precautions like: only surf where you know it is safe, download only if and what you have to, do not open emails before scanning them, and only open them if you can identify the source.
Insure against attacks by blocking all access that is deemed un-neccesary. There are scripts to check how secure you are. I'll post one on the forum later. As soon as I can find it. I have it somewhere, but can't place it right now.

Ok I would like to add few things over here.
You can safely install Norton Antivirus and AVG antivirus...they wont conflict in between...but it is not possible with other antiviruses.(I'm saying this because I've tried it once on my computer and they ran without any problems on my PC)

But If you face any difficulties then you'll need to uninstall both of them and then reinstall the one you want.

There is no harm in trying things...and if both of them run successfully...then you'll be having double protection.

I am currently running Norton Personal Firewall, Norton Anti Virus, McAfee Managed Virus Scan and the Microsoft XP SP2 Firewall. They are all running fine and in harmony with eachother. Each one detects the others and asks which one should be the 'first line of defence' so to speak. As long as you set them all the same it will work fine. For example, Norton should be first to detect a virus (on my setup) followed by McAfee if Norton fails.

Norton generally release updates quicker than AVG so it is technically more secure as long as you download updates frequently enough. I also think that Norton is just an all round 'better' piece of software. It runs quicker and detects more than AVG does.

I think it's possible to install two, as said before, but it can go wrong and two scanners will make your computer much slower i think. So you can try, but maybe it won't work.

As they say Norton releases more updates, but you have to pay for it. I currently use Norton Internet Security 2006 and it works very fine for me. I don't know why you should install both. Ofcourse no scanner stopts all, but Norton stops almost everything and i think anothe scanner would only be anoying.

Well I recommend you to uninstall the AVG Free anitvirus and then Install Norton Internet security 2005. Beacuse it may couse problems with Firewall if the other has one on maybe more things.

So this is what I recommend you.

I guess you can try various combinations with different antiviruses, but that's not recommended... Don’t know much about Norton, but Kaspersky AV will squeak and growl at any other antivirus program installed on your system. Also, think about the resources that you are wasting on running those two AVs! I'm using F-Prot, but I only have it installed on my system, it is not running in real time. I know when a file is suspicious, so I simply do a "RIGHT CLICK > Scan with F-Prot!" It's amazing what you can do to keep Windows XP stable & fast! The very first step on my list is to curb resource hungry antiviruses!

(And the second one is to keep your registry clean and monitor what programs do you have installed on your system. I reinstalled my OS about 4 times during 2,5 years, but I NEVER formatted my HDD for a clean install! So, no Windows XP clean installs, no antiviruses running in the background, and the result? Friends that come over and use my PC are simply amazed with it's speed compared to their freshly installed Windows XP system that is running on a more powerful PC configuration!)

Computers don't make mistakes, you do! Think twice before opening a suspicious file, and you will find out that only one antivirus is more than enough! Also, an antivirus program won't help you when you try to install a spyware "smiley pack" (like the ones on the ads on Trap17), or when you install a buggy program... Your PC will have a mouth full of resource eaters, and your antivirus can't do anything about it! If you really want to keep your sytem safe, you should use Windows Update regulary and keep an eye out for independent AV testing sites (such as http://www.av-test.org/ ), and choose an AV that has the best virus discovery/performance ratio.

PS: Just to make it clear - I'm not hiding in a "rabbits hole"! Don't even think that I'm using my PC for writing letters & documents or playing games! I'm using it for programming, surfing & e-mail and I have loads of different programs installed! And I often run into a great number suspicious websites that bombard you with popups and ActiveX controls!

lol, i had that similar question come up a couple weeks ago. i had NortonAV and McAfeeAV installed at the same time for some reason. They have HUGE conflicting problems, they destroy the programs basically, and it WILL mess up your computer.. i would NOT suggest to install two AV's in the same box. Cost me a pretty penny to get it fixed. Id get a version of ZoneAlarm AV. or if u hate software, you can get a AlphaSheild AV, its hardware. i use both AS and ZA, its ok becuase on is a traffic monitor and one is a scanner, hardware and software.