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antivirus software

by TAXINGBRAIN / January 15, 2009 12:52 AM PST

Can you have more than one anitvirus software programs on your computer at one time.

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yes but not a good idea
by ramarc / January 15, 2009 1:43 AM PST
In reply to: antivirus software

they'll slow your pc down tremendously if they're both actively scanning files/traffic.

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by xxmuppetxx / January 15, 2009 2:02 AM PST
In reply to: antivirus software

I have malwarebyte's anti-malware, spybot search and destroy, ad-aware and superantispyware...My computer is fine it hasn't slowed down in the slightest but I don't have any documents or games or music e.t.c...saved on the computer...
I would recommend you to have 2 antivirus or spyware programns on your computer because if one programn can't find the culprit the other should be able to...we'll that's what I've found out...

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Those mentioned are anti-malware...
by glenn30 / January 15, 2009 2:43 AM PST
In reply to: Yes

Not anti-virus software strictly speaking. Previous poster has it right and recommendation is solid.

Those you mention can be used as on demand scanners for malware. Anti-virus software needs to be actively running all the time... two of them running in real time together can create a problems with each seeking dominance.

Hope this helps.


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In addition,
by MarkFlax Forum moderator / January 16, 2009 7:40 PM PST

I didn't see any specific anti-virus mentioned in that post by xxmuppetxx.

Anti-spyware is OK as it stands, but having no dedicated anti-virus is not a good idea I would guess.


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Re: 2Antivirus Programs
by stevec751 / January 16, 2009 9:14 PM PST
In reply to: Yes

I am using two, Rising and Comodo and both are running at the same time. So far no problems? Steve

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2 antivirus? NO! 2 antispyware? DEFINITELY!
by ust1268 / January 17, 2009 3:40 AM PST
In reply to: Yes

2 antivirus running at the same time is only going to cause problems at some point. 2 antispyware because it seems that one never gets them all. Malwarebytes and SUPERantispyware are 2 highly recommended programs for malware and are both free. Avast and AVG are also free antivirus programs.

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Yes, you normally can but it does depend on which AV ...
by Edward ODaniel / January 15, 2009 7:54 AM PST
In reply to: antivirus software

products you want.

Some will not even install if another is installed and some will not allow the installation of another.

Regardless of whether you get multiple AV apps installed you should NEVER have more than one running in the background (resident scanning) as you are guaranteed to get some conflicts.

It is usually best to choose one AP application then supplement it with online scans such as TrendMicro's Housecall or Eset's (there are others such as Panda but a google search for "on line virus scanner" will locate them for you.

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will cause a conflict
by GENE8 / January 16, 2009 4:06 PM PST
In reply to: antivirus software

In theory, you can. But if you use two antivirus programs at the same time, they will conflict with one another and cause your system to freeze and even crash.There is no need to have two antivirus apps working together, that would be overkill for your system.

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To be truthful, NO.
by PECONET / January 16, 2009 10:13 PM PST
In reply to: antivirus software

Why would you need TWO?.
In this day and age nearly all of the top Anti-virus software (McAfee, Norton, kaspersky), will do the job you need. Unless you like/want to have lots of errors coming up on your system. Keep it simple, just choose one that you like (and it does the job that you want) and stick to it.
I like McAfee, but that is by choice. It does the job and keeps the bugs at bay.
Please post back if you have any more problems or questions.

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Reason for two (or more)
by TheBig3 / January 18, 2009 2:23 AM PST
In reply to: To be truthful, NO.

Different anti-virus apps scan for different segments of the virus, so one might miss one and another might find it. That being said, sometimes one will wrongfully identify a safe, clean file for having a virus. So, if you're worried about viruses having more than one anti-virus would be an extra safegaurd.

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I like this advice.
by R. Proffitt Forum moderator / January 18, 2009 2:33 AM PST

And not for the reason you gave but doing this should result in more machines for my IT industry friends to repair and goodness knows they need the work.

Sorry but for now, my advice for today install just one firewall and antivirus. If you install more than one then go right ahead but be sure you know it might make the machine unstable or sluggish.

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Don't install 2 anti-virus programs
by DKT27 / January 16, 2009 10:26 PM PST
In reply to: antivirus software

Don't install two anti-virus programs as it may conflict each other. Install one like AVG Anti-virus Free. Al through AVG 8 does have anti-spyware but also install Windows Defender(anti-spyware) cause it has many more options like, it allows you to permit the changes that have occurred at that moment of time, ex:- a program is trying to start at computer startup(you want to permit or not) and more. And at last install Malwarebytes' Anti-Malware, free one, cause it is the best anti-malware program I have seen. Because free one does not have live protection it does not conflict with any other programs and is useful in scanning malware only.

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Simple Question, Simple Answer
by Flatworm / January 16, 2009 10:40 PM PST
In reply to: antivirus software


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short answer - Yes
by zepper / January 16, 2009 11:40 PM PST
In reply to: antivirus software

But you only want to use the memory resident features (real-time file and email scanners, etc.) of one of them to avoid slowdowns/conflicts. Sometimes it is hard to prevent them from installing their real-time parts, so if you can't figure out how to prevent, then don't install it. .bh.

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Yes and No
by TheBig3 / January 18, 2009 2:18 AM PST
In reply to: antivirus software

Yes, you can have more than one installed at time. However, you don't want more than one running a the same time. When you install the second and other anti-virus programs you need to disable the "active background scanner", the one that starts when Windows starts and scans files you open, use and download while running your system. Trying to run more than one "background scanner" tends to freeze most of the systems I've worked on. Once I waited 5 hours waiting for a system to finish booting before I realized this was the problem.

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More than one anti-virus software program?
by greg austin / January 18, 2009 4:45 AM PST
In reply to: antivirus software

I know that one anti-virus software program DOES NOT eliminate all viruses. I have spybot on my computer and I shut down "TEA TIMER" (running behind the scenes application) and download (from my usb)7 or 8 more virus programs to detect and eliminate viruses. I delete each program after after I run it and install the next virus software until I've ran them all. Just because software says your computer is clean... don't believe it. run the next one and it will probably detect something that the previous one did not. I only RUN one virus software detector at one time and have my main antivirus(spybot) turned off at this time. I also have a defrag download and 3 free registry cleaners that I use on a regular basis. This keeps my computer running like new. Good luck, Greg nobody

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Yes, But they will Conflict
by NoHeuristics / January 18, 2009 6:25 AM PST
In reply to: antivirus software

Nothing is stopping you from having multiple antiviruses running at the same time, but i advise you not for the reason that they will conflict, resulting in malware getting into your system with out you being notified, This is why i say You Should only Ever have One Antivirus system running at once.

This is the case because if the two anti-virus programs detect the same virus. They will get confused, And will give you a delayed reading when it is too late, or sometimes wont even give you a warning.

Goodluck, NoHeuristics

(McAfee SiteAdvisor Nickname NoHeuristics)

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When in doubt
by pyrrhus55 / January 18, 2009 12:16 PM PST
In reply to: antivirus software

I use 1 anti virus, 1 spyware, the best I can buy. And I keep them current. Various sites have virus comparatives. Here is one:
The problem with having multiple scans at the same time is your system resources. Your robbing your virtual memory, and inviting conflicts between the programs. The programs may actually read each other as a threat. If you believe your anti-virus is not doing it's job. You can either remove it or snoosh it, if offered in options, and run a online virus scan offered through many providers on the net. The online scan also is immune to any infection that actually disables your currently installed anti virus.

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I do not suggest two full AV programs
by 20vtguy / January 19, 2009 12:26 AM PST
In reply to: antivirus software

I'd suggest not having two major AV programs running. For instance don't install Mcafee and Norton on the same machine. Also keep away from the versions that include firewall, parental controls and such. They are more of an annoyance and just slow down your system more. For most users the firewall built into their router is plenty, not to mention Windows XP includes its own firewall software so you should be more then good when it comes to firewall protection. Go with the most basic versions, the ones that only include antivirus and antispyware protection. If you really want an additional program on there for spyware protection I would suggest Malwarebytes from Its free but in the free version it does not give realtime protection so while it won't prevent spyware, its phenomenal at removing infections from an already infected machine. If you want you could upgrade to the paid version and that will give you realtime protection. My suggestion if you really want two programs protecting you in realtime go with AVG Antivirus 8.0 FREE EDITION and pay for the upgraded version of Malwarebytes with the realtime protection. I think they should coexist together on your machine fine. But thats it.

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I think we're mixing apples & oranges, so...
by Hooper74 / January 19, 2009 4:57 AM PST

I think some clarification is in order. I have been doing a bit of research lately so I will pass along what I've learned thus far.

From what I've read, the general consensus is to not have more than one antivirus program installed at a time. However what I'm seeing in this thread is confusion between antiVIRUS and antiSPYWARE (also known as antimalware) programs. These two terms refer to different processes, and are not interchangeable. It is not only acceptable, but is recommended to have more than one antispyware on a machine at the same time. Some people seem to run as many as 4 or 5 of this type of program. So to sum it up you should have only ONE antivirus program, and several antiSPYWARE programs, along with a firewall. And BTW, from what I've read the Windows firewall in XP only offers inbound protection, which is not sufficient. Should you get something on your computer and it tries to call out, you will never know. ZoneAlarm and Jetico firewalls offer both inbound and outbound protection, are available on, and are free.

AVG, avast!, Norton, McAffee, and Kaspersky are all antivirus software. While some or all of these programs do incorporate antispyware protection in addition to antivirus protection there's no harm in supplementing them with one or more antispyware programs such as Spybot, AdAware, Malwarebytes, SUPERantispyware etc. How well these will work together depends on the combination on your system, and is largely a trial & error procedure.

As has been mentioned, you can always opt to use an on-line scanner to scan your entire system to verify your antivirus program hasn't missed anything. One more thing, if you're concerned that your program has given you a false positive you can simply scan that file online for a quick conformation. I've used the site which is a free site which scans your file with 37 different antivirus engines. Hope this helps.

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Active vs inactive
by pyrrhus55 / January 19, 2009 7:27 AM PST
In reply to: antivirus software

If you run a spyware thats actively scaning your PC + another spyware where the settings are to active scan your going to have a slow system. If you run one spyware as active and have a couple more inactively installed then no conflict.By inactive I mean that it does not monitor your surfing but only on request scans your drives for malware. But lets take say AOL spyware scanner (active) + windows defender (active)and run them at the same time??? My experience is that you will slowdown your PC.

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You may be right
by Hooper74 / January 19, 2009 10:45 AM PST
In reply to: Active vs inactive

in running more than one resident real-time monitor creating a problem, but I have Spybot Search & Destroy and WinPatrol running along with avast! A/V with no conflicts on a win98se OS. And I didn't notice any slowdown as I installed them. I think it may depend on the software combinations involved. I tried to install SuperAntispyware and that didn't seem to run right, maybe it didn't like Spybot S&D?

And FWIW I wouldn't use AOL anything! From what I've read (and experienced) their stuff is full of adware, and a real pain to get off your system.

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Not a good idea
by jnamaya / January 19, 2009 8:21 AM PST
In reply to: antivirus software

there is no point of having 2 antivirus software running at the same time on the computer. you probably can do if you are only testing one of them. there is the probability that both antivirus engines will conflict, and slow your computer greatly. you need a lot of memory.

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Anti-Virus & Firewall=No, Anti-spyware & adware=Yes/Maybe
by CKinVA / January 20, 2009 5:00 AM PST
In reply to: antivirus software

Simply put:

Anti-virus & Firewall products are tightly intregrated into the Windows-XP/Vista operating system (ie: they interrupt OS processing calls to verify files, port traffic, etc, and to do so must replace/modify OS modules). Thus: Only one anti-virus and one firewall should even be installed at a time (much less running). If you wish to replace either your anti-virus or firewall software always uninstall the prior product before installing the replacement (MS Windows defender/firewall being the only exceptions).

Anti-spyware & anti-adware products historically have not replaced or modified the operating system thus (usually) several of them could be installed at a time; however, this is becoming less and less true as they are now adding 'real-time' features (ie: Spybot Search & Destroy's "Imunize" and/or "Tea-Timer" features). Installing 'real-time' features probably replace/modify Windows OS files (that may have already been replaced/modified by your anti-virus/firewall products).

It is a big deal to always make sure to uninstall 'real-time' products that could have modified/replaced OS modules in reverse sequence to the sequence they were installed in. If you do not, you may hose over your system and have to re-install the OS (ie: re-format, etc).


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More than one antivirus
by GothicSheep / January 25, 2009 9:20 AM PST
In reply to: antivirus software

Yes, you can, but I wouldn't recommend it. What I would recommended is a basic antivirus and firewall. Then supplement it with anti-malware/anti-spyware.

On my computer, I have Avast Home and ZoneAlarm Basic. I've installed Threatfire recently and it's a good supplement to catching new stuff. So far, it's been efficient.

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Antivirus Software
by UYCH / October 14, 2009 4:03 PM PDT
In reply to: antivirus software

I have norton as my major anti virus software on my main computer. I have also added spybot and lava's adaware. Most professionals that I have spoken to recommend adding on spybot and adaware. They are free and you would not believe all the spyware that spybot picks up that norton misses.

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Norton and Spybot can be a toxic combo.
by R. Proffitt Forum moderator / October 14, 2009 10:22 PM PDT
In reply to: Antivirus Software

Keep an eye out for the usual machine boots in 16 minutes complaint when you mix this and that.

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AV software(s)
by Phil Crase / October 14, 2009 11:34 PM PDT
In reply to: antivirus software

Not generally a good idea can create all sorts of conflicts and unpleasant issues. There are many different trains of thought on what to and what not to do, the discussion (debate) could go on for hours if not longer.

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