PC hangups if running manual scan (v3.8.64263.468)

vista x64 sp1
basically while browsing on firefox it would randomly lock up and slowly loose control of the pc and when trying to stop/pause the scan it would hangup and only way to reboot would be the power button. the pc is virus clean and only CIS is installed along with my windows is slimmed down with vlite and has been optimized in regards to ■■■■ running in the backroundd so im 99% sure its located in the av scanning. i have never used comodo av until now before i used nod32 but since im too lazy to install it i decided to try this out to see the performance differences. so far pretty decent exception of the manual scanning issues which i assume are minor and will be fixed easily. the context scanning issue seemed to already be resolved although i cant really give much more details on it since it is random and i cannot provide any further logs/details on it.

Heres a additional screenshot of the error after 9 hrs of no one touchign to PC during the scan. the scan does not finish and the Context Manual scan will say that the Scan engine is not initialized like before i had applied the new patch as described in a previous thread.
https://forums.comodo.com/anti_virus_bugs/comodo_antivirus_engine_not_initialized_on_vista-t34222.0.html

[attachment deleted by admin]

upon reboot the scan engine is back to normal so its only manual scans breaking the scan engine…

I have had the same problem. Vista with SP1, full CIS (latest 3.8) but no other security apps. I did a manual scan and it ran Ok for I while. I then started thunderbird when it was still scanning and things immediately started to freeze. Eventually I resorted to the power button as even ctrl-alt-del did not work.

More info: I think running Thunderbird is a red herring. I also had the “virus engine not initialised” error and corrected that by copying bases.cav and updating again. I then tried a full scan again and it froze a second time while scanning a small png file. I think it was also a png or other image the first time. The main Comodo interface that is already running still runs when it the computer freezes and works OK but no new programs may be started. Again it had to use the power button. I can scan an individual file or folder OK but it looks like png files are making it freeze and when it freezes it has a catastrophic effect on the whole computer - rather dangerous.

I can confirm as this just happened to me.
Vista Ultimate x64 Sp1, CIS the only security program active, proactive, AV enabled.
Could not terminate the scan, could not run anything else either.
Reset was the ONLY option to break the hold.
Surprisingly, the CPU usage meter showed only 6%, and memory was not increased. HDD activity was minimal also.
I was doing a Windows directory scan.
My scan froze on the file c:\windows\syswow64\twnlib4.dll

This sounds like the same problem.

My guess would be that when the scanning froze, defence+ also froze and prevented anything from being checked and so nothing would run. Things already running were sometimes OK but nothing would start up.

so x64 issue? i assume it can be recreated and if so will there be a hotfix or a new release when fixed? in mean time ive just disabled to av scanner until the minor issues are worked out. if any more details are needed they can be provided.

my manual scan froze too (on x32 system)…the timer was still counting though but it was just stuck on a particular file (sorry I forget what the file name was) the scanner would allow me to click on pause scan and then stop scan…it asked if I was sure I wanted to stop scan I clicked yes…then both pause and stop buttons greyed out. After this I couldn’t get rid of the scan box…ctr alt del didn’t work and trying to manual reset the com didn’t work. The only way to get rid was to power off.

Win XP home sp2 32 bit system
CIS only (latest v.468) db 980
I didn’t have this problem with the older version .439 of CIS

ps I do have another com xp home sp2 32 bit and that scans fine

When I am doing a scan the HDD activity is always 100%! When I stop the scanning, my HDD actitivity is almost 0%! This problem was also present in older versions of CIS, I am using now the latest build (CIS 3.8).

I hope the devs are testing cavs and can reproduce the disk usage issue, so they can fix it…

Edit:

the scans also take a very very very long time, despite the scan engine is super fast… (this could be related to the disk usage issue) The scan could be taking well over 3 hours… But I can’t really tell because I do not let a scan finish…

Having similar problems on my 64-bit machine during the manual scans. It will hang up and cmdagent crashes. Then AV isn’t even loaded.

Wait a second… You are scanning the files on your HD. That means you’re continually reading the files from your drive! I would expect HD usage to be at or near 100% if you are running a virus scan. This is in no way anomalous behavior.

Do you mean that your CPU usage is 100%?

3.8 was a huge improvement for me. Version 3.5 scans took in the neighborhood of 4.5 hours on my system! Needless to say, this was just not feasible and I didn’t do any full scans with it. However, after upgrading to 3.8, my system is scanned in 48 minutes. This brought the AV scanning engine right in line with every other AV scanner I’ve used.

I still get the freezes with 3.8.64263.468 with XP64bit. It won’t complete any manual or scheduled scans.

Mine is on Windows Vista 32 bit.

I still have this problem on 3.8.64739.471. The antivirus scan is unusable. It lock up after about 60000 files on a small image file which is one of the icons for filezilla. Used the power button to get out of it again.

In case it helps, I have proactive security with image execution control set to maximum and dll added to the files to control. Vista SP1 32 bit. No other security applications running. I have UAC on. Problem occurs is starting the scan from administrator account or limited user account.

I appear to have solved the problem by completely uninstalling CIS, cleaning out the registry and deleting all traces under program files and then reinstalling and importing my old setting. I can now do a complete computer scan.
:BNC

My mistake, problem not solved. I did a second scan as limited user and the problem reoccurred. Could not even start task manager, everything on my PC was blocked.

Hey, I think this is because CAVS has a heavy load on your disk… So the disk usage is constantly 100%, this is causing a lock up and slow performance of your pc… That is what I am thinking.

its nto that it locks up the pc its that its permanently locked and not finishing the scan. it cant be due to poor performance because i am aware of when my hardware is having issues and currently everything is stable. my config is on a raid 0 hitachi 1tb 32mb hitachi setup with a extra hd for the pagefile i dont believe a AV scan should be stressing the hd to the point where its locked up compared to majority of other scanners. even with the newest update the pc still locks up and you must wait abit to stop the scan. also the firewall is not displaying connections in the connection viewer i just noticed… looks like comodo messed some things up with this newer release… oh well considering they released a update in under a week i assume a new one will be out in about the same amount of time fixing these minor issues.

Disk activity is low when it locks up. I think it is defence+ blocking everything from running. Programs already running are ok for a while. It looks like they lock up then they need to ask defence+ for something.