System Hangs after Comodo Antivirus Installed

Hi I am new to Comodo today. I run XP Home on a 2.6MHz PC with 1.25GB ram.

I downloaded the firewall (recommended by my ISP Exetel Australia) and antivirus software. I removed Norton products from my PC, rebooted, then installed the firewall. After rebooting all seemed well so I installed the antivirus and rebooted. Again all seemed fine so I started to check my PC for viruses. After some time I realised that there may be more up to date Av files so I cancelled the system check and performed an update. I kept getting errors saying that the product was performing other activities that needed to close before I could proceed. I closed all open windows but kept getting the error message. After some time a message appeared saying that updates had downloaded and I needed to restart my PC. I did this and Windows booted but became VERY sluggish and just hung. Even Ctrl-Alt-Delete did not function. There was limited access to buttons as windows booted but once the Comodo icons appeared in the system tray all ground to a complete halt. I could move the cursor but got the hour-glass pointer when placed over any part of the system tray, no applications would start if clicked on and the Start menu would not open if left too long after Windows start. I performed over a dozen hard resets but the result was always the same. If I went immediately to the Start menu after booting it was sluggish and the searching torch gif played instead of listing my applications.

To resolve this I had to un install Comodo AV. To be able to do that I had to call up the task manager with Ctrl-Alt-Del immediately that Windows booted and end all Comodo process trees as they started (files with names C*). Only then was my windows able to complete its boot and I could use the Control Panel to remove Comodo AV. I am still using Comodo Firewall and all seems fine.

I have been reading some other posts. Not sure if they relate to my exact failure mechanism so did not want to hijack those threads. Reading those posts it seems that I have not completely removed Comodo AV - and in fact the directory and some files are still on my PC. I will follow instructions left by others to completely remove those files.

I just wanted to report the error that I witnessed and provide the work around to recover from it. I would like to hear from Comodo if this is a known problem with a fix. All files were current - downloaded today (29.01.2007).


Hi Mike, welcome to the forums.

I’m sorry you’ve had trouble with CAVS, I assume that the version you had problems with was CAVS 1.1 beta. I also experienced exactly the same problem with that version, as did others. Comodo are aware of this issue & have taken steps to correct it. However, all these fixes are in the new CAVS beta I can recommend CAVS beta over the previous beta, as it much improved & more stable. More details of CAVS Beta, its new features & download link are available here. In order that you can see other users experience of the latest beta, the bug report topic for this version can be found here.

I hope that helps.

I watched this AV installed on someones system and it bogged. It was an old laptop running Windows 2000 so I figured that was the problem. I installed it on my kids computer - a fresh install of XP Pro - and it worked just great. I then installed it on my Father’s computer, which is a fairly new HP system, and it bogged even though I had uninstalled any previous antivirus(Trendmicro). Since I now couldn’t use his system I had to keep shutting it off. While trying to decide what to do with it I figured it may be a fluke and installed it on his laptop after uninstalling Norton AV program and rebooting. It also bogged. There are occasions that it starts right up and runs fine, but most the time it bogs so bad it’s unusable and has to be shut off. I have let it sit for 15 hours and it still didn’t finish booting up. The odd thing is that you bring up the task manager(which is quite a task since most keys are dead) and it doesn’t show the resources at any higher than 4%. But each click or refresh of the screen is about 10 minutes in between. I hate to uninstall your product, but this seems to be an issue with more than just one system. That’s 3 of 4 I’ve seen it on. That’s pretty bad odds.

This sounds like CAVS beta 1.1 again. If this is the version you have tried I can understand your problems.

However, the latest beta available on these forums (CAVS Beta) is vastly superior and I have installed it on about 15 systems (only two are mine, the rest are friends who have been impressed since the last version two beta) so far without any problems.


Actually it was whatever is from the Comodo home page. It was so strange because the taskmanager only showed like 2-5% of resources being used, yet it was dogged to uselessness. Let me finish this story so that if anyone has this same problem this may help. I had blown away the IBM laptop and reinstalled everything again as a new system, but the other two I couldn’t do that with. This was a Toshiba laptop and and an HP desktop mind you. Since it happened on both I racked my brain to come up with the reason or some kind of link between the two. The ONLY think I could think of was that each one in it’s history had Norton installed on it. The desktop had been running PCCillin for the last couple of years, but before that it was Norton and the laptop had Norton uninstalled to install Comodo. Being that Norton was the only link I decided to run a complete search, including hidden and system files, of any files that would still be on the desktop. I found only 2 Norton files. So I deleted those two. Ran a Semantic search and found nothing. I then reinstalled Comodo and restarted. It came up perfect. No problem at all. I ran the updates and it’s running just fine. So over to the laptop I go and just try the reinstall again on it without changing anything. I had the exact same results as I did previous on that system and it was now useless. I tried rebooting several times to no success. I then went in under safe mode and ran that same search I had on the desktop. The laptop too found 2 Norton files. I deleted these two. I then restarted my system and it came on without any hitch. Both systems now run perfect. If a virus is something that is put on my system that can affect it adversely to a point of uselessness then I would have to say that Norton gave me that virus. I’m glad to be done with them FOREVER! (:CLP)
Scott :SMLR

tnx for that info, Scott.

Do you happen to know/remember/have on record the names of the two Norton files that would appear to have caused the trouble?

Or, if you can describe how you found and removed the files?

It may be helpful to other users…


PS: Anderow’s right, too… the current Beta 2.x is much improved over 1.1. Better scan engine, less resources, more stability, plus an application-based HIPS.

I wonder if Symantec’s Norton Removal Tool would have removed these files - I used it to attempt removal of some leftover Norton files last year and it did not remove them all as stated on the Symantec tin.

I am afraid I eventually got rid of the files manually and can’t remember what they were but I remember something about a worm removal tool that was difficult to get rid of. Wish I could remember…


Yes I had EXACTLY the same problem after replacing Norton with Comodo Antivirus 1.1 - but after removing it with the very useful removal tool on the forum, so far the latest beta version is working perfectly…