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  1. #1
    5 Star Lounger
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    Ignorant question:

    if , after downloading an AV program and doing an initial scan, and if the program runs in the background, why does one have to perform new scans?
    (I use Avast! Free But assume most AV program are pretty similar)

    Thank you.

  2. #2
    Super Moderator jscher2000's Avatar
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    [quote name='acerfmayer' post='785823' date='22-Jul-2009 13:20']if , after downloading an AV program and doing an initial scan, and if the program runs in the background, why does one have to perform new scans?
    (I use Avast! Free But assume most AV program are pretty similar)[/quote]
    Most AV threats should be intercepted by real-time scanning. However, scheduled scans may detect files that were missed in a real-time scan because detection did not yet exist for that malware. If there were a way to ignore 3-year-old files, that probably would improve the efficiency of scheduled scans, but then it would create a way to evade detection, so...

  3. #3
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    [quote name='jscher2000' post='785824' date='22-Jul-2009 16:32']Most AV threats should be intercepted by real-time scanning. However, scheduled scans may detect files that were missed in a real-time scan because detection did not yet exist for that malware. If there were a way to ignore 3-year-old files, that probably would improve the efficiency of scheduled scans, but then it would create a way to evade detection, so...[/quote]

    Makes sense. Thanks for the clear explanation.

  4. #4
    Plutonium Lounger
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    [quote name='acerfmayer' post='785823' date='22-Jul-2009 16:20']... if the program runs in the background, why does one have to perform new scans?[/quote]
    I also use Avast and haven't done a drive scan since the first one when I installed it. I agree with Jefferson that "real time" scanning should keep us protected and it HAS in my case. There are occasional times when I will manually scan one or more files immediately after downloading to make sure Avast doesn't find anything suspicious. (I use the right-click method within Windows Explorer.)

    So far I've been lucky!!! . . .

  5. #5
    Plutonium Lounger
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    [quote name='acerfmayer' post='785823' date='22-Jul-2009 21:20']...if the program runs in the background, why does one have to perform new scans?[/quote]
    The real time scanner has to be written so that it has as little impact as possible on performance. The scheduled scan can use more resources and is sometimes able to detect additional threats.

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