Cannot open file and slow on-demand scan in 5.0.677

[KaniSDragon]

I've been slowly working through scanning the entire hard drive of another computer over a network share using the on-demand scanner (right click, choose "Scan selected items for viruses").  For some reason, if I try to scan the whole system it scans for awhile and then reports "Error: The system cannot open the file (4)" on a ton of files.  So I started scanning one directory at a time.  When a directory has these errors opening files, I choose a subdirectory or a smaller set of files and try again until it works.  Sometimes retrying the scan two or three times on the same set of files will eventually complete without errors.  It seems very random.

I gradually worked almost all the way through the whole drive and suddenly Avast was taking like 30 seconds to open its scanner window.  The more files I scanned, the longer it took to open the window.  Eventually it got so slow I would sometimes hear the chime indicating the scan was done and then the window showing the scan was done would open 30 seconds later.  Two reboots did not help.  I also rebooted the machine I was scanning and the router.  Even scanning a tiny file on my C drive before connecting the network share to what I was trying to scan took forever.

When AvastUI is frozen or not appearing, if I look at the task manager I see that "AvastUI.exe /nogui" is using up 50% of the CPU (100% of one dual-core)

The main avast UI opens quickly when I click the Avast icon in the task bar.  I can switch between different tabs and settings quickly, except when I choose the "Scan computer" tab, it takes about a minute to show anything (the whole window turns white in the mean time).  If I then click the "Scan logs" subtab, again it takes a minute or even longer.  I see a lot of logs here and I'm assuming that it's the number and size of these logs that's causing the slowdowns.  I could probably choose to delete the logs and fix the slowdown, but I wanted to report these bugs and see if the developers want copies of these logs or anything before I delete them.  Until then, I'm continuing my scanning using Avast on my laptop which is running at fast speed.

My system is Windows 7 64bit, 4 gigs of memory, Intel E7600 CPU.  I have not had any other antivirus software installed.  I'm running Avast Internet Security 5.0.677 with a 3-PC license.

[Pondus]

Have you tried to check for malware with Malwarebytes ?

Malwarebytes Anti-Malware 1.50 http://filehippo.com/download_malwarebytes_anti_malware/
always run update before you scan so you have the latest database
click the remove selected button to quarantine the infections found
please post the scan log here

[KaniSDragon]

No, I haven't run any other antivirus/antimalware.  After being hit by a pack of dozens of malware installed through a Java or PDF exploit triggered by simply visiting a web page (not clicking anything), I do all web browsing in a virtual Ubuntu machine to avoid such infections and I hadn't installed anything new when the slowness began to occur.  I would rather not install anything other than Avast - I don't believe I should need to use or buy two different products and deal with the resulting slowdowns or conflicts.

The malware I got infected with before (on another machine) got past eset's nod32 and I later duplicated the infection on a virtual machine and found that Avast protected against it, which is why I use it on this machine.  I understand there will always be infections that one antivirus will find that another won't, but the threats with any significant number of vicitms should be seen by any decent product within a month or two.  The fact that nod32 did not protect against this major exploit in Java/PDF after it had been around at least six months was a major point against it.

[SafeSurf]

Since you have a 64-bit machine, you cannot do an Avast boot-time scan with the current version, however this will change with the newer version(s) coming out in the future.

You can also try doing an Avast Repair first (assuming this is NOT malware) to try and fix your problem:
- Go to Control Panel > Add/Remove programs > Avast Antivirus.
- Scroll down and choose Repair function in the pop-up window.
- Reboot.

If this fails to fix your problem, then we need to look for malware as a possible cause.  You can still get malware many other ways these days unfortunately.

In the meantime, what Pondus (the previous poster) was suggesting with MBAM, was that this is a free on-demand scanner that works differently than Avast in checking malware.  Many of us use it here and it does not conflict with Avast; it gives us a different opinion and we use it to help diagnose problems. 

If you could please run Malwarebytes’ Anti-Malware (MBAM) to give another opinion for malware:
·   Download free http://www.malwarebytes.org/ (the blue button) for an on-demand scanner.
·   Double Click mbam-setup.exe to install the application.
·   After install, click update so you have latest database before scanning.
·   Under Settings:
o   General: Automatically Save File After Scan Completes is checked off
o   Scanner Settings:  Check all boxes
o   Updater: Download and install update if available is checked off
·   Once the program has loaded, select "Perform FULL Scan", then click Scan.
·   The scan may take some time to finish, so please be patient.
·   When the disinfection scan is complete, a log will appear in Notepad and you may be prompted to Restart. (See Extra Note).
·   Click the “remove selected” button to quarantine anything found.  You will find the infection details under the Quarantine tab.
·   The log is automatically saved by MBAM and can be viewed by clicking the Logs tab in MBAM.
·   Copy & Paste the entire report in your next reply.

Please let me know if you have any questions.  Thank you.

[KaniSDragon]

I realize there's some tiny possibility the slowness is being caused by malware, but based on what I described above, isn't it far more likely that it's the size of the logs causing the slowdown?  As I said, I wanted to know if one of the Avast developers wanted to look at my logs to address this bug before I delete them.  If nobody from Avast reads this or is interested, I'll just delete the logs and I think it will most likely solve the slowness problem.  If that doesn't fix it, I'll reinstall Avast.

As for the error in opening files over the network, that could be a bug in the Samba implementation on the Ubuntu 9.10 machine I was scanning, or it could be another Avast bug, or, I guess, malware on my machine, however unlikely.  Since I don't need to run scans of other machines very often (this was of a friend's machine which is now returned to the friend, having found no viruses), I'm not overly concerned about the bug at the moment.

[SafeSurf]

Here is information on how to invoke a memory dump file:  http://support.avast.com/index.php?_m=knowledgebase&_a=viewarticle&kbarticleid=71.

Please, zip and upload the C:\Windows\Memory.dmp file to this anonymous ftp server and name it uniquely: ftp.avast.com/incoming.  You may want to also include a link to this thread.  Avast will analyze it and respond back to you in this thread or to your email.

Let me know if you have any additional questions.  Thank you.

[schmidthouse]

Hello KaniSDragon:
Just a side note....You may want to hide your 'email' as sometimes scammers will visit the forum and attempt to harvest email addresses. If you go to your profile and edit your preference to 'hide email from public' it will still be available for Avast helpers but not the general public

[DavidR]

Not so much scammers (e.g. people), but there are bots, that do nothing but trawl the internet looking for email addresses to add to spam lists.

[schmidthouse]

Not so much scammers (e.g. people), but there are bots, that do nothing but trawl the internet looking for email addresses to add to spam lists.

Thank you DavidR...I stand corrected

[Para-Noid]

1) Hide your e-mail address.
2) What are your scan settings? Are you using default settings or have you tweaked the settings?
3) What else is running on your computer?
4) Are the files password protected?
2, 3, and 4 will affect the scan.

[SafeSurf]

I realize there's some tiny possibility the slowness is being caused by malware, but based on what I described above, isn't it far more likely that it's the size of the logs causing the slowdown? 

There is always the possibility and that is why several of us here have given you suggestions for running scans with Avast and MBAM as a precaution.

As I said, I wanted to know if one of the Avast developers wanted to look at my logs to address this bug before I delete them.  If nobody from Avast reads this or is interested, I'll just delete the logs and I think it will most likely solve the slowness problem.  If that doesn't fix it, I'll reinstall Avast.

Since it sounds like you had your mind made up for submitting the mini-dump files, I provided you with the information of submitting this.  Please post back in this thread when you hear back from Avast regarding this matter.  Thank you.

At this point, we need to wait until the OP hears back from Avast regarding his mini-dump submission.  Thank you for everyone's input.