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Can I have multiple antivirus software on my computer.

by jeffrey_broadbent / January 22, 2007 3:52 PM PST

OK, I am very new to computers and the only advice I got was from the shop keeper. Thanks to this foram I've learned a great deal. Thankyou. What I have learned so far about security is I can only use one firewall, and I can use multiple anti ad/spy/mal software. Can I use multiple anti-virus software? If I can only use one active program, can I use other software just to do regular scans but have them switched of at other times?
My System:
Notebook, Windows XP home
Norton Anti-virus 2006 paid version, with firewall
Ad Aware free
Windows Defender
My plan is to get rid of Norton, because it hasn't done anything at all. I will download a free firewall. eg Zone Alarm or Comando. I will download some more free Anti spyware software so I will atleast have 3-4. Now I just have to think about Anti-virus. Can I download 2 or 3 anti-virus programs, have one as the active one, and the other just to do regular scans. Thanks. I don't mind paying out some cash, but freebees would be prefered.

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Re: multiple anti-virus
by Kees Bakker / January 22, 2007 4:32 PM PST

It's exactly like you write. You should only have one antivirus active to do the real-time scan (free ones are Avast, AVG Free or I think Antivir) but you can use more than one for the occasional full scan.


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Virus Software..
by castingRod47 / January 22, 2007 6:21 PM PST

You can only RUN one type of Security Software..
usually in McAFEE your get the Firewall and Anti-Virus/
there are also more Comprehensive Packages for Internet Shopping..
When I DownLoad the Subscription from McAFEE it automatically Turns-Off Windows Firewall..adding the McAFEE Firewall..
Then the Subscription RUNS for a Year($$40.00)Updateing my PC..
The Comprehensice Package RUNS about $$70.00..
I have tried the ISP-provided software../I really prefer the Subscription..
And the New Microsoft version of Security Software has me wary also..
I find it difficult to trust the FREEBIES../I've tried the Spybot..its virtually worthless..since it doesn't know what its SCANNING../its just scanning relentlessly..I have RUN multiple SCANS and it would FIND the same(questionable)Problem(??)each SCAN..
I find it can't be TRUSTED..the others...I rely on a UPDATEING SERVICE..and in five years McAFEE has Defended my PC for a reasonable rate..
The decision in my opinion/
Is all about Internet Shopping..
and McAFEE has the edge.

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virus software-Avast Anti virus
by buggzee / February 2, 2007 6:55 AM PST
In reply to: Virus Software..

This is a free program for home use. It is great! I have it on 2 computers, my desk top and my lap top. It automatically updates itself, and it does catch viruses.

I also use Sygate free for home use firewall. I find it works much better than Windows or Norton.

Best of all, both of these Home programs are free.

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by santuccie / February 2, 2007 8:18 AM PST

Sygate is the old name. They were bought out by Symantec.

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Are you selling McAfee?
by copsblow247 / February 13, 2007 8:26 PM PST
In reply to: Virus Software..

People like castingRod47 here don't really have a clue (blind leading blind) and give advice anyway! McAfee, Norton and Trend Micro along with most of the other big names all SUCK! If your computer comes with a trial version of it - It is CRAP!
Now with that said, if you want to buy one program that covers pretty much everything, get Zone Alarm Security Suite, learn to use it and be done! I still run Spyware doctor with it(just in case)

This combination seems to work pretty well (running both spyware programs can slow computer)

Firewall - ZoneAlarm - Free
Anti-virus - Avast - free
Anti-spyware - Spyware Doctor(PC Tools)- my favorite (faster)
Spysweeper(Webroot) - Now can be bought with Sophos

Other stuff that comes in handy
Registry Mechanic - registry protection
Advanced System Optimizer

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speaking of big names, and "blind leading blind"
by santuccie / February 14, 2007 7:37 AM PST

As long as ZoneAlarm remains one of the most widely used firewall products, its IDS unit will have to continually grow bigger and bigger in order to cover new attacks as hackers work to get around it. Especially when its IDS is the closest thing it has to inbound protection.

I have been posting all over CNET that simple application firewalls (like ZoneAlarm) are little more than outbound protection. Unless you have a hardware firewall in front of it, it will not be able to protect you from incoming hacker attacks. People who use WiFi in areas where everyone else uses WiFi are ESPECIALLY vulnerable, as infected neighboring machines can be commanded to crack their WEP/WPA encryption and spread the disease, easily punching right through simple firewalls once inside the target network. The only thing ZoneAlarm really has going for it is its IDS/IPS, which you can more than make up for with the free version of Novatix Cyberhawk, a standalone HIPS unit.

If you intend to use the Internet at all, you have to open some ports and protocols in order to receive the information you're requesting. That said, I recommend you use a firewall that is capable of protecting those open ports. SPI (Stateful Packet Inspection) firewalls can do just that. Four such firewalls I've used are Kerio, Safety.Net, Jetico, and BlackICE. Again, some people like ZoneAlarm's extra features, but you should only use this product if you already have a hardware SPI firewall (all dedicated hardware firewalls have SPI) in place.

Speaking of antivirus, I strongly disagree that the one in ZoneAlarm Security Suite is better than McAfee. ZASS uses Computer Associates' VET engine, which is one of the very slowest to release signature updates, and doesn't seem to make up for this in heuristics. Sorry copsblow247, but even McAfee beats them any day of the week IMO. I can't say much about Sophos, as I haven't been in much contact with it. However, I am of the understanding that the Sophos AV component in Spy Sweeper is on-demand only, so you definitely need some real-time protection. Avast! is actually pretty decent in my book, but there are others. Of late, I've been using CyberDefender for antivirus and antispyware protection.

Most novice to intermediate PC users would assume the best registry cleaner is the one that finds the most "problems." However, what the vendor doesn't tell them is that some of these may be false positives. Your system registry is a critical thing, and there's no room for aggression here. You'd be far safer with a conservative product that confines itself to unambiguous errors, even though it might leave a few obsolete entries behind. Be aware that a few orphaned entries hanging around are far less likely to cause a bluescreen than vital entries that have been removed by an aggressive product like Registry Mechanic. I recommend EasyCleaner or the reg cleaner in System Mechanic on quick cleaning only.

Similarly, I have also seen the comprehensive method in Advanced System Optimizer crash a few machines, so try to resist this tempation if you do decide to use it. Stick with the quick and conservative optimization method.

As far as the other names mentioned (Spyware Doctor, Spy Sweeper, and KILLBOX), these are all good IMO. Spy Sweeper is probably the best when it comes to real-time protection, while Spyware Doctor might be a nose ahead when it comes to post-mortem, on-demand scanning. I have nothing against KILLBOX, but I prefer Unlocker myself (it doesn't require nearly as many reboots).

Norton is the biggest target on the market, and it and McAfee are both resource hogs these days. I'd have to differ with the stated opinion that Trend Micro sucks, but I'd also say, "Why buy the cow if the milk is free?" in this case. Take advantage of their HouseCall scanner periodically, which is one of the most popular on-demand scanners these days. Of course, popularity means it has the bad guys' attention as well, but I'm not talking about proactive protection here, so you might as well use it when your browser can reach it (some malware will try to block you from accessing Trend Micro's or Ewido's [AVG Anti-Spyware] online scanners).

Hope this helps!

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by santuccie / February 14, 2007 7:41 AM PST

I said, 'Unless you have a hardware firewall in front of it, it will not be able to protect you from incoming hacker attacks,' referring to ZoneAlarm. I should say that it will block some of them, but only when closed ports are being probed. ZoneAlarm monitors the programs that access the Internet, as well as the ports and protocols they use; it does not monitor the content of that traffic, which can easily come from unsolicited connections. SPI and DPI firewalls do.

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Just so you know....
by jdoggmcsquishy21 / March 3, 2010 10:38 AM PST

Just a little info. Be careful of today's Microsoft Updates on machines that are using Zone Alarm Free ( Version 7.0.462 ) after rebooting the Zone Alarm client will block almost every web access with an alert. Still investigating and trying the newer 7.0.473 version to see if it will rectify the situation.

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Yep, That's An Old Issue That Was Fixed By ZA
by Grif Thomas Forum moderator / March 3, 2010 1:13 PM PST
In reply to: Just so you know....

Installing either 7.0.483.00 (NOT 7.0.473.000) or later versions such as ZA Free or ZA Free will fix it.

Hope this helps.


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Free version of Avast Virus Software
by buggzee / March 14, 2007 12:02 PM PDT
In reply to: Virus Software..

I've used this software now for 3+ years, and I now have it on 2 computers, a desk top and a lap top. It works great! It automatically updates the virus data base, and it catches viruses in e-mails and on websites if you try to send them thru e-mail.
I scan my computers often and if a virus has gotten thru it will find it and delete it.

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Most Security Companies Recommend..
by Grif Thomas Forum moderator / January 23, 2007 8:35 AM PST

..installing only ONE antivirus on the machine at a time.. Many, such as the newer McAfee and Norton, won't install if another antivirus program is resident on the machine. Read the information in the links below for other major worldwide companies and universities (reliable sources) that feel the same.:

Sophos Antivirus Instructions. Answer to General Question number 2: '' 2) I would like to have 2 AntiVirus Programs installed on my computer. Would that provide better virus protection?''

See the "IMPORTANT" statement at the bottom of the "Step 3: Use Up-to-Date Antivirus Software" in this Microsoft article:

Read the first sentence below the heading: "If you already have antivirus software on your computer":

Read the main topic number 7: ''Occasionally Run Online Virus Scans'':
Simple and easy ways to keep your computer safe and secure on the Internet

Hope this helps.


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by santuccie / January 23, 2007 2:33 PM PST

For resident protection, you can only have one antivirus at a time. Personally, I use AVG Free. It's not the best, but it's full-featured and doesn't require annual re-registration.

For on-demand scanning, you can use as many as you wish, with system resources being your only real limitation. Two of the best on-demand scanners you can get for free are BitDefender and AntiVir.

By the way, do you use a desktop e-mail program (like Outlook), or do you use webmail? If you simply do your e-mail on the web, you might actually consider using AntiVir as your primary protection.

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You only need one anti-virus
by mutton777 / January 24, 2007 9:45 PM PST
In reply to: recommendation

I have found AVG free, one of the best. it includes an e.mail scanner
in addition to AVG, all you really need to keep your pc running smoothly is to download C. CLEANER, SPYBOT SEARCH & DESTROY, AND
AD-AWARE, all free. I have never needed anything else.
Go to PITSTOP to check your computer out.

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dig a little deeper
by santuccie / January 25, 2007 8:36 AM PST

In case you didn't know, a clean scan doesn't mean your system is clean. All the software I use is free as well, but it's considerably more powerful than your Ad-Aware and Spybot. Classics they are, but they started falling behind in 2005 and continue to do so. Neither of them could ever remove a polymorphic or process-injecting Trojan, whatever they might SAY they can do.

Instead of CCleaner, I use CleanCache. Before that, I was using DCleaner. I would never recommend CCleaner to a newbie. It's default settings are aggressive, and you should never use a non-dedicated product to clean your registry.

I could give you a list much longer than just PITSTOP to check and see what's on your machine. In addition, I use HJT. The sooner you can stop the critters from crawling, the better.

Like I said, the reason I was using AVG Free is because it's full-featured. It is by NO means the best antivirus scanner, but the fact is that viruses are the least common these days. Spyware is much more prevalent, while Trojans now make over 60% of all malware. We're playing a different game now: hackers and malicious programmers aren't looking for notoriety, they're looking to make money off your machine. Naturally, it follows that they would be trying a LOT harder. I'm sorry to say, but the sources you've been consulting are rather old. I am constantly fixing machines, and it's my job to be current on these things.

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As you may have guessed by now, the answer is "no".
by Paul C / January 25, 2007 6:23 PM PST

So, let me tell you what I do:

AVG Anti Virus.
Zone Alarm firewall.
AVG Anti Spyware (formerly Ewido). All of these are free and work well.

Since spyware, trojans, etc. are more of a threat these days than viruses, I also use Spybot, but almost solely for the Immunize function. I also use the freeware Spyware Blaster, which works somewhat like Spybot's Immunize, but has a different database (common among antispyware apps). Unlike antivirus programs, you CAN run multiple antispyware programs; in fact, I recommend that you do, if only to regularly scan with them.

Online virus scans are worthwhile running occasionally; I use Panda, but they all seem to do OK.

I will pay for some apps; one is Iolo's System Mechanic, which I run in lieu of CCleaner, as I've found the latter is too aggressive in its cleaning, as others have noted in this thread.

And just in case, I do make regular backups using Acronis True Image (I don't mind paying for backup software).

Hope this helps.

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some details for ya
by santuccie / January 27, 2007 4:17 PM PST

Paul is on the right track, but allow me to elaborate. ZoneAlarm is one of the best application firewalls in existence, but I would not use it unless I had a hardware firewall in front of it. It is not an anti-hacker firewall. Any open ports are unprotected, leaving you wide open to attack.

In addition, WiFi users are particularly vulnerable. If a wireless-enabled computer within range of your router is hijacked, which is not an uncommon thing, its botmaster can make it crack your encryption and get inside your network rather easily. Even if your router has a built-in firewall, it will no longer stand between you and the bot in your network, leaving your machine(s) face to face with danger.

Use Kerio. It's user-friendly, and unlike ZoneAlarm, it will protect ports even when they're in use. To make up for ZoneAlarm's powerful HIPS, install a dedicated HIPS unit. Novatix Cyberhawk is one of the very best, and it comes in a free version. The only thing it lacks is threat removal and rootkit scanning, but it can still prevent and permanently block such threats until you take them out with a scanner.

Paul is absolutely right about viruses being the least prevalent these days. Malicious programmers rarely seek notoriety anymore, they seek to make money off your machine. Spyware is everywhere, while Trojans now make up 60% of all malicious programs. That said, Spybot is just not enough to protect you. While you can still avoid most dangerous infections with a competent firewall and a bit of discipline, you should never assume you're safe when trouble is out looking for you.

AVG Anti-Spyware and a-squared are the two best anti-Trojan products available, according to AV-Comparatives (AT-Comparatives in this case), the foremost authority dedicated to the testing of antivirus/antimalware products. Coincidentally, both of these offer free scanners, both of which I'd recommend you run once a week at least. Trojan Hunter was also a contender in the AT-Comparatives test, but they withdrew after seeing their results. While I couldn't get an actual number from Mr. Clementi, he did inform me that it was "much lower than Ewido, A-squared, and Digital Patrol," the top three.

Panda ActiveScan is a good scanner, and recently added a rootkit scanner to it. The most popular, and considered by most to be the best, is Trend Micro HouseCall. Note however, that some malware will actually block you from running Trend Micro, and I've heard that they're blocking Ewido's (AVG Anti-Spyware) online scanner as well. So it's good to have a copy of AVG Anti-Spyware on your machine at all times. And if you happen to find that Trend Micro cannot run, you can use an alternate link like this one:

I use System Mechanic myself, and am quite happy with it. And I don't know where I'd be without Acronis. As easy as this program makes it to backup your operating system, it is worth every last penny of the $49.99 it costs. However, if you don't need the function of backing up to DVDs, and would be content with a recovery partition on your hard drive itself (which is quicker and easier to restore from), you can register for a free copy of version 7 here:

By the way, there are two programs I know of that both contain antivirus components that will work with a conventional one, although viruses really aren't the greatest threat you have to face. These are Spyware Terminator and CyberDefender. Spyware Terminator could well be the best freeware antispyware out there right now. Windows Defender is said by to have a slightly higher detection rate, but I've found its resident monitor to be practically useless, and I've rarely ever seen it find anything while other products have. Spyware Terminator has much stronger real-time protection, and I have seen it find stuff. Its "auxilliary" antivirus I mentioned is Clam.

CyberDefender is a product that I'm expecting to see revolutionize the security industry. It's an all-in-one "seamless" product, integrating antivirus, antispyware, anti-spam, and anti-fraud into one contiguous unit that is supposed to "play friendly" with a conventional antivirus. But I see no need for it.

CyberDefender only came off the rogue list at Spyware Warrior a matter of months ago. In addition, they just started offering this freeware version. You will see a couple of negative reviews about it right here on CNET, but you'll see a couple positive ones as well. Mine is one of them, and it explains how the product works, if you care to look it up. I have recently replaced Windows Defender and AVG Free Antivirus with CyberDefender, and have had no need to clean up tracking cookies or anything else since. When a threat is detected, CyberDefender automatically alerts me and asks me what to do with it. Happy

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Sure about that?
by Phil M. / February 3, 2007 2:30 PM PST
In reply to: some details for ya

"AVG Anti-Spyware and a-squared are the two best anti-Trojan products available, according to AV-Comparatives"

The most recent anti-trojan comparative to be found on, as I write this, was done in March of 2006 (almost a full year before you posted your message). What's more, the product was not "AVG Anti-Spyware", but rather "Ewido".

I am aware that Grisoft purchased Ewido and renamed it to AVG Anti-Spyware, but it is no longer the same product, no longer the same version, internal changes have been made, and competitors have also changed, and new competitors appeared.

So, calling AVG Anti-Spyware the "best anti-trojan" in January, 2007 is ridiculous.

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by santuccie / February 3, 2007 2:56 PM PST
In reply to: Sure about that?

I'm well aware of the new name, and I'm also aware of how long it's been since the reviews. But in answer to your question, I have removed plenty of Trojans with it since then, particularly since October, which was only four months ago.

Did you happen to see the margin in the AT-Comparatives? Pretty large, don't you think? TDS-3 is gone, and until Trojan Hunter decides to add some black-and-white signatures to their rulset database, I think my opinion still stands? Ridiculous? I think not.

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by santuccie / February 3, 2007 4:09 PM PST
In reply to: yes

AVGAS' database continues to steadily grow, and is indeed the self-same database that existed in "former" class-leading product Ewido. In fact, it has since overtaken even a-squared's database in size.

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Using multi anti-virus:
by Atvrunnerboats / February 1, 2007 9:09 PM PST

The answer is no, and if you're running Norton, get rid of it, it's no good, I had Norton 2000, and it was always giving me problems, so I bought the Norton 2006, and it was the same, it would not destroy some viryses, so I installed AVG Free Edition, and "whamo" it destroyd all the viryss that Norton couldn't, so in a nutshell get AVG, and you will be safe,, as far as I'm concern AVG is the best one of all, it even has an email scanner.

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(NT) Symantec NIS
by wat3rboyewt2 / February 3, 2007 12:57 AM PST
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RE:Syamnatec NIS post
by wat3rboyewt2 / February 3, 2007 1:26 AM PST
In reply to: Symantec NIS

Okay, I was interrupted and lost the text of my post by AVG7.5 updating. I had said that I wanted to improve my security and purchased Norton Internet Security package. After many e-mails to tech support and problems installing it, I asked for and rec'd. a refund. I then used AVG free and liked it so I purchased the AVG 7.5 Internet Security pkg. with all the trimmings. It discovered 2 trojans that the AVG free missed and many cookies other programs had missed. Downside is that it is a little bloated and slowed my OS down some. It also is sometimes unpredictable (like losing text during an update). Sometimes I'll uninstall the virus detector and do my stuff, reinstall it and scan. It also "heals" a toolbar I like so I have to reload it everytime I scan. Overall, it's a good package and I feel I don't need anything else. Combined with a little common sense, it gives me a feeling of security.

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Right or wrong this is what we do
by shyguy1 / February 1, 2007 9:11 PM PST

First it's interesting to note that Norton is still the same old Norton. Just as an aside you may want to go to Majorgeeks or search for the utility that's supposed to remove Norton completely. Otherwise, in the past it was everywhere on your computer.
OK, we run AVG free edition and then run TrendMicro HouseCall scan every couple of weeks. All are free and so far so good.

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Simple solutions?
by Says Who? / February 1, 2007 9:57 PM PST

Hi Guys,

I realize that the industry is constantly changing - but what is the most practical S.I.M.P.L.E. solution?

I am sick and tired of juggling four or five programs to try to ensure my PC is safe.

Real tired of complex answers...

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running multiple anti virus pgms
by miklb / February 1, 2007 11:21 PM PST
In reply to: Simple solutions?

not a good idea ... i suggest completely uninstalling Norton, download the AVG FREE edition from Grisoft then SpyBot & AdAware (also free) ... i have been happily running these 3 for years.
hope this helps, miklb(:o)}

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practical, simple solution
by santuccie / February 14, 2007 12:52 AM PST
In reply to: Simple solutions?

I used to use AVG antivirus, but now I use CyberDefender. I would give you a blurb on their recent history and such, but to keep it simple, I'll let you check it out on their site. Let's just say it's like having a computer forensics expert by your side at all times (CyberDefender gets updated in about an hour for everything suspicious it detects). It's AV, AS, anti-spam, and anti-fraud. I've been using it for a few weeks or a month now, and it really works. Anyway, I'll shut up and cut to the chase:

- AV/AS/anti-spam/anti-fraud: CyberDefender
- Host Intrusion Prevention: Cyberhawk
- Firewall: Kerio

These three will protect you from just about everything. It's all I use now, and it works better than my old solution.

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NO !!!
by Ecm / February 1, 2007 11:12 PM PST

Simple answer from recent experience.

Download all you want, but running two or more Anti-virus programs at the same time will cripple (significantly slow down) your computer.

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Let me clarify...
by Says Who? / February 2, 2007 12:09 AM PST
In reply to: NO !!!

OK let me restate my question once again with specifics...

I am using XP Firewall, Trend Micro PC cillin, Webroot Spysweeper, Windows Live Onecare.

Is this overkill? If so what to lose - what to keep?

All are up to date and paid for.

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RE: NO !!!
by Ecm / February 2, 2007 1:43 AM PST
In reply to: Let me clarify...

Yes, you need a firewall, antivirus, and spyware programs, I don't have any experience with Windows Live Onecare so can't speak to that. If you have network hardware that has a hardware firewall, you should use that. I have a hardware firewall in my wireless router.

I refer specifically to running multiple anti-virus programs at the same time being a problem. Having different anti-virus, spyware, and firewall programs is not a problem that I am aware of. I currently have 2 spyware programs (one because it was pre-installed on the machine) running simultaneously on the same machine without a problem.

Personally I use (and am happy with) Zone Alarm Security Suite, which I have used since it was introduced, and Zone Alarm before that, for a number of years. It is nice to have everything in one package and not having to do multiple updates and juggle multiple licenses. My opinion.


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by Says Who? / February 2, 2007 1:52 AM PST
In reply to: RE: NO !!!

Thanks, they just seem to overlap and trip over one another at times. They all want to frequently update which makes dial-up a royal pain. But it seems everyone assumes that 1-40 MB updates are no big deal (probably because they all have DSL at home and work!). I agree with you. One suite would certainly be better, but it seems no one company has ALL the ducks in a row.

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