Every time, when i get into D:\Backup in my hard disk, Avast begins to consumes 100% CPU and large amount of memory, and this leads often to hanging up my computer (Stop responding), so i have no option but to reset the computer.
This continues even after i leaves that folder.
Why this is happening???
What’s on D:\backup, besides the blindingly obvious, e.g. is this a recovery partition or a partition/folder with many compressed files ?
You also don’t say what type of scan you are doing, nor what the scan settings are ?
e.g. Quick, Full or Custom scan or any changed setting within the scans, Sensitivity, Packers, Scan all files, etc. etc.
Which avast…??
Which version…??
Which OS…??
I use Windows 7 SP1 and Avast free 6.0.1203 (I can’t change nothing in my profile other than the Account related settings).
My Avast begins to do this when i randomally get into this folder, which contains setup files of my programs and drivers and backups of Firefox data.
Other security related software installed…??
Windows Defender.
Hmmm…
Did you maybe change the initial avast! settings…??
I changed the initial settings of my Avast.
How did you change them? 
What if you scan the D:\Backup folder on-demand (e.g. from the rightclick scan from Windows Explorer), without entering the folder - does the same happen?
The scanning don’t cause this problem.
When i simply enters the D:\Backup folder, Avast starts to consume 100% CPU, and as i stay longer in this folder, Avast consumes more CPU resources and begins to swell, in terms of memory usage and the computer gets slower.
If i continue to stay in this folder and to enter the subfolders or to run files from it, the problem got even bigger, eventually results in computer hanging up.
I setted Avast that it will scan all files and archives on access. However i don’t find any reason for this, to cause Avast to consume 100% CPU and hang up the computer in a specific directory.
This looks to me more like a bug in Avast.
Does it work, after you reset avast…?? (SETTINGS - Troubleshooting)
I don’t want to reset Avast setting to factory default, because this can’t be restored and this will delete any scheduled scan that i created.
Sorry, can’t help you then.
Maybe igor has any better ideas.
Good luck…!
Well, if you set all files to be scanned on open, and even all archives to be unpacked by the File System Shield… then it shouldn’t be that surprising.
I mean, when you enter the folder, the file manager might start touching the files - so avast! has to scan them, and it may take quite a while for some archives (and certainly impose a heavy load on the machine). The load may start delaying other things the OS wants to do… and that’s what you see.
When my Avast begins to consume 100% CPU, when i reaches D:\Backup folder, my HDD don’t become busy and the main Avast screen displays that Avast isn’t busy at all with scaning on access.
However a process called Sf.bin appears occasionally randomally in the task manager and takes 50% from the 100% usage of the CPU that Avast uses at that moment.
That’s the emulator… meaning something is being unpacked.
Sf.bin is part of avast. (code emulation)
Also the process of Avast that takes 100% CPU when i enters D:\Backup is AvastSvc.exe.
Sorry, but don’t you understand what we’re telling you here…??!
Change your settings.
Problem solved. 