RESOLVED !!!! Avast Boot scan - very slow especially on PDFs

[Stang]

I had a malware-gen infection that Avast found in an old restore file.  It was moved to chest.

I tried to schedule and do a boot scan but after about 1 hour it was still at 1% and it seemed that PDF files took 5  to 10 minutes each to scan so I aborted the scan.  MBAM is clean.  Avast scans clean now.  aswMBR shows boot disk is clean.  Everything looks fine.

Question is why does the Avast boot scan go so slow on PDF files?

[Stang]

Boot scan finally finished.... took about 15 hours for 54Mb of hard disk.  Seems like this changed in Version 6.  It was much faster in the prior versions. 


Anyway, I am disease free. 

[johnnyjohnny]

I had something like this happen last night, but it wasn't an boot-up scan. I had previously backed-up the contents of an 8GB flash drive to my W7 PC (running Avast! free edition), and was trying to copy the backup to a new 16GB flash drive. The copy started out normally, estimating 16 minutes to copy, then 30, then 3 hours. The file it was trying to copy at the time was a moderately large PDF (10MB). I checked back after 15 minutes and my PC was still trying to copy the same file. I thought that the flash drive was defective, but I first tried copying only portions of the backup to the drive (which coincidently had no pdf files in it), and that went quickly. I tried copying another portion of the backup (this time containing pdfs) and I saw the copy slow down while copying a couple of pdfs and then speed up again copying other files.

Lastly I tried copying over the last folder in the backup - this one had the problem pdf from my initial copy attempt. The copy process once again seemed to stall on the same pdf. At this point I got suspicious and disabled the Avast! on-access scanning, and the copy completed normally.

I'm surprised that Avast! seems so capable at scanning zip files and installers, but bogs down on pdfs. I'm wondering now if there is anything wrong with my 8GB flash drive, or if it was just Avast! slowing down the copy process as I made the backup.

[Stang]

Were you running Avast version 6?  It might be my imagination, but it seems like this slow PDF issue started with V6.

I wonder if anyone from Avast can chime in .... maybe it it doing a more thorough PDF scan in the new version or something.

[johnnyjohnny]

Yeah, I upgraded to 6 a short time ago, and I'm reasonably sure that the problems occurred after the upgrade.

I haven't looked into the scanner settings, but I'm inclined to turn off pdf scanning since a) nearly all of my pdfs are datasheets from reputable sites; and, b) I don't use acrobat reader to view them.

I recommend STDU (http://www.stdutility.com/stduviewer.html). It is awesome and free.

[dispatcher21]

This also happened to me.  Windows 7 64bit, Avast 6 updated.  Tried to move a 16MB pdf over my network and it stalled out.  Disabled Avast on the target computer and it zipped right on. 

[Stang]

Looks like my problem was fixed by virus definition 110401-2.... I now run like before.

Thanks to whoever found and fixed this issue.