why cannot install two different antivirus software in the same machine?

Discussion in 'Virus Information' started by javacc2, Jan 24, 2006.

  1. javacc2

    javacc2 Guest

    I have Mcafee antivirus software installed in my machine, and I tried
    to install Norton antivirus software, but it pops up an error message
    "Norton AntiVirus has detected a conflicting anti-virus product is
    already installed and prevents this installation from proceeding." Do
    you know why we couldn't install two different anti-virus software in
    the same machine?

    Please advise. thanks!!
    javacc2, Jan 24, 2006
    1. Advertisements

  2. Because AV uses some undocumented approaches in order to have complete
    control over all events in OS. They create kernel mode componentes that
    tracks file activities (CreateFile(W|A) hooking), dll injection
    (WriteProcessMemory hooking) etc. So it's hard to have two AV's properly
    working in one machine.
    Scherbina Vladimir, Jan 24, 2006
    1. Advertisements

  3. javacc2

    Malke Guest

    Sometimes you *can* install two separate antivirus programs, although
    you should not *run* two antivirus programs at the same time. Both NAV
    and McAfee install system services and are designed to run all the
    time. If you want two antivirus programs installed on the system (and
    it really isn't necessary), then find something other than NAV for the
    second one.

    Malke, Jan 24, 2006
  4. I forget to mention the "marketing" part of this approach.

    Every AV company treats another AV companies as competitor, so even if
    Norton is compatible with McAfee (I don't know for sure, it's just an
    ideas), they don't want you to use McAfee, instead buy another Norton
    Scherbina Vladimir, Jan 24, 2006
  5. Hi.

    First it is not a good idea to post with your real email address (assuiming
    it is real) because you are now likely to fall victim of SPAMmers(unsolicated

    Then ,you really don't need more that one antivirus software.As described by
    the others they are incompatiable and if you somehow install second they will
    definitely work incorrectly.

    Choose which one to use -either McAfee or Norton (make sure they are always
    updated and their versions are current -2005 or better 2006 versions)

    Then if you would like a second opinion about your security and malware
    status ,you a online scanner.

    Panda Software free Active Scan will be great

    Learn how to protect your computer:

    If you have malware problems and your security softwares are useless :

    =?Utf-8?B?UGFuZGFfbWFu?=, Jan 24, 2006
  6. Along with what the others have said, you also have the possibility of
    the first antivirus corrupting the second one, and vice versa. What I
    mean by this is, the data files that the antivirus compares your
    programs to, contain snippets of virus code (signatures). So, the two
    antiviruses will try to remove each other's data files.

    You also run the risk of the two antiviruses causing your system to bog
    down, while they are scanning files. And, you risk having to reformat
    your computer, because one or the other will corrupt your hard drive
    enough that it won't boot.

    Really though, if you've been using McAfee and want to get rid of it,
    you should completely uninstall it before putting on Norton's or any
    other antivirus. If for no other reason, then so you can have a clean
    test of the new choice. Otherwise, how will you know whether any issues
    you have are related to the new antivirus or the fact that you've got
    two of them running at the same time.

    Patrick Dickey, Jan 24, 2006
  7. Along with what the others have said, you also have the possibility of the
    Signatures are placed not in binary files, most likely there're placed in
    some *dat files with own formats, so antivirus "A" cannot read / analyze
    database of antivirus "B".
    OS provides syncronization in it's internal layer, so when two or three
    applications calls DeleteFile on the same file, OS will syncronize these
    True :)
    Scherbina Vladimir, Jan 25, 2006
  8. javacc2

    Ian Kenefick Guest

    Yeah - proprietary formats are used... but isn't there a problem with
    the way Panda encrypt their antivirus database files. I've read in virus
    bulletin that they are not completly encrypted and this leads to false
    detections by other vendors.
    Ian Kenefick, Jan 26, 2006
  9. javacc2

    Bigbruva Guest

    It might help to explain that most AV apps have two main elements:

    1) Real-time scanner
    2) On-demand scanner

    The real-time scanner is typically the most problematic for multiple AV
    installations. This is because they are designed to intercept incoming files
    and data and scan them as they arrive or depart the system. If you have two
    AV programs attempting this it will slow the system down and can cause
    unpredictable behavior as both scanners attempt to control the data.
    Two On-demand scanners are usually okay together as they are typically run
    one at a time so as long as they don't detect the other AV scanner as a
    virus (as Ian mentions in this thread) they will simple scan the local hard
    disks for malware.

    As Panda_man points out your could always use an online scanner for a second
    opinion if your where to suspect a single scanner was missing something.
    Also http://www.virustotal.com/flash/index_en.html is an excellent place to
    check suspect files against most of the main AV packages.

    I hope that helps explain the issues clearly for you

    Bigbruva, Jan 26, 2006
  10. I don't that for sure (never used Panda) but such problem is not major and
    can be occured with *any* executable that has in memory signatures that
    treats by Panda as a virus.
    Scherbina Vladimir, Jan 26, 2006
  11. But why would you want to? Once a product has your confidence, you are
    capable of learning how not to get it infected. It is better to
    excersize and wear a tee shirt than to slouch in two coats.

    I would like the opportunity one day to take XP out for a spin and
    really put it through its paces without stepping in dogczd all the
    time. Wouldn't that be nice.

    But the OP's question has not been answered except as some sort of
    conspiracy on the capitalist's side. As if the people who keep
    Microsoft up and running ever get paid by them. (OK they gave Patrick
    Kollah, the owner of SpyBot a copy of Windows once. That must have cost
    them maybe as much as 2 cents to do. I bet the postage cost more.)

    For a firm to make money producing AVware they have to be on the ball
    at all times and get the right answers quickly and then they need to
    produce patches and get them out into the wild to combat the viruses.

    Before they can make any money selling theire product they need to be
    well known and they need to have a track record. But that's just
    business. I imagine a gang of friends setting themselves up as good
    guys with a hobby then a reputation. Then a small business.

    They are the good guys, they don't have the time to go up against other
    AVmakers. They need to keep a complex system up and running with all
    the add ons and peripherals that all the different manufacturers make
    going on at the same time. There is no way all AVs can be on the ball
    all the time.

    Sometimes their patches cause problems and they need to patch their
    patches when they get feedback. If they have to unscramble the
    spaghetti that is produced at the same time by other antivirus writers,
    the time it would take would be phenomenal.

    Then someone would come along and work out a way to get the two search
    engines to blow a fuse. That would flatten a substantial segment of the
    internet perhaps.

    As with all explanations the simplest one is usually the right answer.
    I'm not saying I'm right. Norton is or was recently mis-identifying
    Spybot and resisiting straightening things out. Personaly I think
    Teatimer isn't worth having.

    The simplest course then, is not using it and the simplest course with
    most antiviruses is to keep things simple and just use the one that
    suits you.
    Weatherlawyer, Jan 26, 2006
  12. javacc2

    Guest Guest

    I use Kaspersky and F-Secure with Sophos, seems to work fine
    Guest, Jan 26, 2006
  13. javacc2

    Ian Kenefick Guest

    You do know that F-Secure uses Kaspersky engine also right? And both are
    superior to Sophos with regards to detection capabilities.
    Ian Kenefick, Jan 26, 2006

    3 antivirus softwares?????????????????????????????

    =?Utf-8?B?UGFuZGFfbWFu?=, Jan 26, 2006
  15. It's ok, I also was playing with some AVs installing them together. If
    you're lucky you will see BSODS not often :)
    Scherbina Vladimir, Jan 26, 2006
  16. All files are binary.
    It's how you interpret the binary that decides what a file is.
    Brian Gregory [UK], Jan 26, 2006
  17. Under binary I ment executable. Sorry for cofusion.
    Scherbina Vladimir, Jan 26, 2006
    1. Advertisements

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.