Avast On-Access Scanner Scanning Every Single File

[angela23]

Hi Everyone
I have been using avast for a year now and I've found it to be excellent but lately it has started giving some problems. It scans every single file that I access on my computer even if it is a plain text file (.txt). Even if I need to open a text file or an image file I have to wait for a few seconds before I can access it because avast scans it for a while and then allows the access ... I can see the Icon revolving every time I access any file. It used to run very smoothly before this problem appeared. I understand that it is necessary to scan executable files and the likes but what is the purpose of scanning text files and image files which do not spread any virus. Is this normal? or has my copy of antivirus become corrupted or some settings changed? Please help me.
Thanks in advance.

[MAG]

avast scans all documents (OLE files) on opening by default - not sure if this would include txt files - even if it was scanning a txt file on opening a few seconds sounds like quite a long time to do it.

A few simple things you could try - if they don't work report back and wait for some more expert help.

Under file system shield expert settings, scan when opening, - is 'scan all files' checked?

Avast repair - control panel, add remove programs, avast, change/uninstall, repair.

Reset to factory defaults under settings - troubleshooting (unless you've spent ages setting up complex custom settings for exclusions etc)

[Lisandro]

txt files aren't OLE (documents) and shouldn't have any problem while scanning.
Can you post the file name and path?

[angela23]

@mag, thanks for the suggestions. No, "scan all files" is not checked. Also, .txt files are mentioned in the exclusion list but the program still scans them. I haven't tried the re-installation yet because I want some easy way out of this. By re-installing I will lose all the virus database updates and I will have to download those again.
@Tech, thanks for replying. Its not just a single file. Every file on my computer is scanned on access whether it be a text file or image,sound or video file, files which have nothing to do with viruses. It is really strange.

[igor]

If you only see the icon rotating, you cannot say what is actually being scanned - might be something in the program that's making the access, not the file itself.
I'd suggest to open the File System Shield page and watch the "Last file scanned" field at least...

[MAG]

I haven't tried the re-installation yet because I want some easy way out of this. By re-installing I will lose all the virus database updates and I will have to download those again.

avast repair option isn't a re-install - it won't affect your virus definitions (or at least it never has for me) .

[Tetsuo]

Hi,

Same problem here. Avast! scans .txt files too - although I don't have to wait for a few seconds before I can access them.

I checked all the settings, everything seems ok: "scan all files" is not ticked and .txt files are mentioned in the exclusions (however "execution" in not ticked).

I have ticked the option for PUP and the Euristic scan level is "High".


I opened the File System Shield page and watched the "Last file scanned" field, .txt file are reported as "filename.txt.lnk" or, depending on your windows settings, "filename.lnk".


Thanks and sorry for my English,
T.

System Info:
Win Pro SP3
Avast Free AV 6.0.1125 ***Behaviour Shield removed
Online Armor Free 5.0.0.1097

[angela23]

@mag, i didn't have to repair avast. The problem is now solved but through a different method that i am mentioning below.
@igor, thanks for the reply. Avast was scanning every single file on accessing it. The problem was not with Avast, it was the explorer.exe file that was behaving strangely due to some rootkit spyware that recently infected my computer. So I ran the combofix utility which detected the actual malicious program and eliminated it except that during start up, the explorer.exe began executing twice and the "windows explorer" window appeared on the screen  after loading of desktop icons completed. So I checked in msconfig startup list but could not find explorer.exe mentioned anywhere so I ran the combofix utility once again and now even that "windows explorer" window has stopped appearing on start up. I guess the problem is solved because Avast is running pretty smooth as it used to run before the infection.
Thanks everyone for all your suggestions.

[Pondus]

what is the purpose of scanning text files and image files which do not spread any virus.

http://www.mcafee.com/us/mcafee-labs/resources/threats-faq.aspx#6

6. Can JPEG, GIF, and other image files be infected?
Yes. Some software programs have vulnerabilities that contaminate JPEG files with malicious code. Contaminated JPEG files can carry or launch a virus, worm, or Trojan on unpatched systems.

http://www.bleepingcomputer.com/forums/topic128812.html

[Tetsuo]

Out of curiosity, could someone please open a .txt file and then open the File System Shield tab in Avast! and check the "last file scanned" field? Is that .txt file  reported there?

In my system .txt files are reported as "filename.txt.lnk" (or depending on your Windows settings, "filename.lnk").

Thank you very much in advance

[miscreant]

Out of curiosity, could someone please open a .txt file and then open the File System Shield tab in Avast! and check the "last file scanned" field? Is that .txt file  reported there?

In my system .txt files are reported as "filename.txt.ink" (or depending on your Windows settings, "filename.ink").

Thank you very much in advance

I can confirm last file scanned name is.ink ...shown when opening a txt file on my system.

[igor]

Scanning of .lnk files is certainly correct and wanted.
However, why should you have a shortcut for every text file, that I don't know...

[DBone]

Mine says "notepad.lnk" after opening a text document with the default MS notepad.

[igor]

Notepad.lnk, if you're opening the document e.g. by drag&drop on Notepad shortcut on desktop... sure.
However, a lnk file to the text file, not to the Notepad executable... is different.

[Tetsuo]

However, why should you have a shortcut for every text file, that I don't know...

I don't know but on Windows XP SP3 all the .txt files that I open with the default Notepad (double-clicking the file) appear as "filename.txt.lnk" (or, depending on your Windows settings, "filename.lnk") in the "last file scanned" field.

Is this normal? :/

Thank you all again.