I just ran a full system scan and upon completion I noticed that avast said it had scanned 21.5 GB, but according to Explorer directory, my only partition, Local disk (C:), has a total capcity of 18.6 GB, with 11.7 used and 6.9 free.
How could this be? ???
Because avast counts the amount of archive files (.zip, .cab, etc.) so the total size could be larger than the total file size itself.
I don’t understand. How can avast say it scanned 21.5 GB when I am using only 11.7 GB? It is even saying that it has scanned more than the total drive capacity. :-\
Because an archive file is compressed and avast has to unpack them to scan the contents, it counts the size of the files it unpacks to scan, assuming you have selected to scan archives.
If you clicked local disks and also selected folder selection and clicked C: then it could also cause duplication of scanning. These are all suppositions as you haven’t provided much detailed information about the typo of scan and its settings.
I’ve answered before… into zip archives there are files, these files have a size, this size is counted in the total amount scanned…
I am running a Thorough Scan (I called it a full system scan). I select local drive only and do not select any folders. Yes I have “Scan archive files” selected. If I uncheck it, will that eliminate scanning of .zip and .cab files and reduce the size of the Thorough Scan?
Also, is it a good idea to not scan archive files?
Thank you
Yes.
Archive files are inert, a virus can’t harm inside of an archive file. When unpacked, the file will be caught by the Standard Shield. So, you can scan archive files eventually. Maybe monthly only.
I figured if I was a malware writer (virus, trojan, worm, rootkits, etc) I would attempt to hide the executable file in a folder where it is not expected to be found. Would an archive file be such a place? Many security applications, as you know, have quick scans that look only in the most common places that malwares hide. It always seemed to me that this practice could be easily exploited. What do you think?
Yes it will. When unpacked will be detected (so we hope that).
avast Home does not allow such customization. You could do it in Pro (configurating Tasks).
Well an archive file isn’t really a hiding place as files can be seen and if necessary scanned, and if you download that zip from the internet the chances are the Web Shield would find it, because it scans all content on port 80 http. So it really isn’t a hiding place.
The quick scan deals files classed as dangerous (immediate danger), the Standard scan deals with possibly dangerous files and Thorough, everything all you can elect to scan archives, see image extract of avast the Help file.
Archive (zip, rar, etc.) files are by their nature are inert, you need to extract the files and then you have to run them to be a threat. Long before that happens avast’s Standard Shield should have scanned them and before an executable is run that is scanned. Thorough is also by its design very thorough and perhaps a little overkill for routine use, were a Standard scan without archives should be adequate.
I can report that my Thorough scan without archives showed 14 GB scanned, whereas the same scan with archives showed 21.5 GB. So the number did decrease significantly.
That was a helpful .gif you attached, DavidR. I did not know how to adjust the scans between Quick, Standard and Thorough. Now I do! Thank you.
I am having trouble, however, moving the slider on the Resident Scanner sensitivity, either by pressing the button (as directed by the pop up) or trying to move the slider itself. These settings appear to be Disabled, Standard or High. When I say I am having trouble, I mean no change is apparent after pressing the button or trying to move the slider. The GUI seems to hang or freeze and finally when I press another button on the console, the Resident Scanner Senstivity slider finally has moved. It is very balky, or sticky. Does this sound right? I don’t think so.
If you had been able to select Thorough then you should be able to select Quick or Standard (the default) as you are moving the slider to the right for Thorough and left to Quick.
Click the Details… >> button to get a detailed view, select the provider you want to adjust. But a word of advice, don’t go tinkering with the settings without first reading the avast help file, resident protection section.
Thank you for the attached images. They were helpful. I am referring to trying to adjust the Resident scanner via the GUI console.
In the image below named Thorough scan, I access that by pressing the button on the upper right of the console (Local disks).
In the image below named Resident scannerI, I accessed by pressing the avast icon button middle left.
In the image below named Resident scannerII, you see the slide bar for the Resident scanner.
What I am trying to explain, as noted above is…
I am having trouble moving the slider on the Resident Scanner sensitivity, either by pressing the button (as directed by the pop up) or trying to move the slider itself. These settings appear to be Disabled, Standard or High. When I say I am having trouble, I mean no change is apparent after pressing the button or trying to move the slider. The GUI seems to hang or freeze and finally when I press another button on the console, the Resident Scanner Senstivity slider finally has moved. It is very balky, or sticky.
IMHO, that shouldn’t really be used as the Resident Scanners should really be changed in the On-Access Protection the GUI is for the on-demand scans and I don’t know if any changes made there are only good for the duration of the on-demand scan.
There shouldn’t need to be any requirement to adjust the resident on-access scanners for an on-demand scan.
See image for the view you would get when you click the Details button of my previous image.
I agree with you, that “there shouldn’t need to be any requirement to adjust the resident on-access scanners for an on-demand scan”.
I was unaware that the place to adjust the Resident Protection was viewed by clicking “Less detail” on the Standard Shield window. Now I am thinking that they are one and the same… Resident Protection & Standard Shield.
Thanks for your help and advice.
You’re welcome.