Conflict with Avast Free Antivirus?

Comodo Internet Security - CIS Install / Setup / Configuration Help - CIS
1

I am using Avast Free Antivirus 5.1.889. Everything was fine until the new year, when both Avast came out with a new version and Comodo came out with a new version of their free firewall. Since then I have had problems with the two programs working with one another; basically, each time I install a new version of the Comodo firewall (the last one being version 5.3.45685.1236), Avast turns off protection and I am unable to turn it back on.

I am attaching a screenshot of what happens to Avast after installing Comodo Firewall. If you see where it says “Fix Now”, I’m sorry to say but clicking on that button does absolutely nothing. The only way to fix the problem that I know of is to uninstall Comodo firewall and use the built-in Windows firewall; however, I don’t like the Windows firewall and would like a better third-party firewall.

I am sending this also to Avast support in hopes that someone has the answer to this problem.

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2

I suggest an avast installation from scratch:

  1. Download the latest version of avast! Uninstall Utility and save it.
  2. Download the latest avast! version and save it.
  3. Uninstall avast from Control Panel (if possible). If, for any reason, you can’t run it, try booting in Safe Mode and doing it from there. Anyway, boot after that.
  4. Run the avast! Uninstall Utility saved on 1. If, for any reason, you can’t run it, try booting in Safe Mode and doing it from there. Anyway, boot after you’ve run it.
  5. Install avast! using the setup saved on 2. Boot.
  6. Register your free copy or add the license key for Pro.
  7. Check and post the results. If, for any reason, you did not solve, try doing the step 3 in Safe Mode anyway.
3

This is a known issue in Avast 5.0 and 5.1, and has nothing to do with CIS. The Avast shields shut down twice on my wife’s laptop using only the Windows firewall. A fresh Avast install is necessary to get Avast working again.

You could try adding CIS to exclusions in Avast, but that didn’t help me on three out of five systems of mine running CIS.

Good luck.

4

As much as I like both Avast and Comodo, I’m afraid I ended up having to uninstall Comodo Firewall until the known issue gets resolved. On a fresh install of Windows XP, with a fresh install of both Avast and Comodo, Comodo was blocking Avast’s Web Shield protection efforts. Thank you everyone for your help.

5

Hey and warm welcome to comodo forums jmac2point0ne!

Have you tried to add Avasts exe file in exclusions of Execution control settings (CIS —> Defense+ —> Defense+ Settings —> Execution control Settings —> Detect shellcode injections (i.e. Buffer overflow protection) —> Exclusions —> Add —> Browse…) and to add it in application rule in the firewal (CIS —> Firewall —> Network Security Policy —> Application Rules Add —> Select —> Browse… Now you have search for the wanted file)

Try to see if this helps.

Regards,
Valentin N

6

I may just give that a try, as the firewall I chose to use (Online Armor) in place of Comodo is… well “annoying” would be an insult to those applications that are truly annoying. LOL. Thanks for the tip!

7

I am sorry to hear that but if you try I would like to know the result of my tip.

Regards,
Valentin N

8

I think you have misread my post, there is no known issue between Avast and Comodo. The known issue I referred to is that Avast shields randomly shut down, but that is solely an Avast issue.

9

I have just reinstalled win XP SP3 on a laptop five times in 2 days, because windows explorer was acting sluggish. Each time, when several windows were open, it took a lifetime to close them down. :-TD

I kept checking other stuff like hardware, configurations etc, and even upgraded the RAM to 2GB! Same difference!

I even began to wonder whether I had a corrupt file somewhere on my install disk. I tried another install disk and it came up with the same problem.

Then I remembered having problems running comodo 5 with the latest Avast sometime last year, so I uninstalled both programs. Tested it again, windows explorer was OK. :-La

Since I usually put Avast on first, I decided to put Comodo on first this time. Voila, no problem - windows explorer was acting fine. Then I put Avast on again, back to square one, same problem.

Somewhere on the net, someone is pointing a finger at Avast’s web shield as the culprit. I haven’t tested this yet, so I can’t agree or disagree with him. Right or wrong, I’m just passing on the tip…

Well Avast has had to go, and I am now using Avira (free). Works like a charm. :-TU

On my other machines, the very latest Avast and Comodo are working OK, just this one, I can’t for the life of me figure out why it’s given me so much hassle.

If I ever get round to testing individual Avast components to see whether they conflict with Comodo, I’ll keep you posted.

aka red mist

10

Tried this as best I could, but still ran into the same problem. Thanks anyway. :slight_smile:

11

It’s just really bizarre that the problem started happening right around the start of the new year, when both Avast and Comodo released new versions of their programs. Prior to that, I had no problems whatsoever. But if I had to chose one over the other, I chose Avast.

I tried two other firewalls: Online Armor and ZoneAlarm. Both have their pluses and minuses but neither one did what I needed it to do entirely. ZoneAlarm came close until I found out there was an issue with ports (a topic outside the scope of this post).

I was really happy with the Avast/Comodo combination. The main reason I’m not going with Comodo Antivirus is because of the learning curve. I’m not a guru, but when it comes to the two basic needs every internet user needs – antivirus and a firewall – I have to insist on the KISS principle. For that, I am satisfied with Avast.

I’ve since come to learn that my router has two firewalls built in, so for now I am not using a software-based firewall (other than what comes with Windows).

Doing a fresh install of Windows XP SP3 this time around has truly been a learning experience, and I do thank everyone for their suggestions.

12

I think that’s an avast issue so you have to tell them so that they fix it. Try to uninstall Behavior blocker or whatever it’s called.

Regards,
Valentin N

13

avast newest verson for web shield still has some kinks in it for some people Regardless of what firewall your using. They eventually have it worked out :slight_smile:

14

I should mention this on my own thread (the one a few posts (at the moment) ) down about problems with the cavshell.dll shell … before changing back to Avira, I did have Avast on the problematic (with Comodo not being able to install) before the change …

basically i was trying avast for awhile … .also had Comodo 5.0x … i Upgraded (the version # /app … not just the AV DB) of Avast … then removed (with Revo uninstaller … i didn’t just delete files … i KNOW BETTER than that … due to a family emergency I was able to get on a family member’s high speed connection and I got both x32 and x64 of 5.3 that was brand new … I went to install and it told me to remove (ok i may have goofed up at this step but its typically no big deal) 5.0x so i did … after that (Avira now installed once again and no Comodo IS) … I went to install Comodo IS 5.3 (or 5.03?.. whatever) … with the intent of no “GeekBuddy” and no “AV”… just the firewall and Defense+ … I always get to … well … you can read my problems https://forums.comodo.com/install-setup-configuration-help-cis/problems-when-installing-cis-53-related-to-av-shell-t68349.0.html here … I am just wondering since I did that Avast Upgrade in mid January … I have had issues with Comodo (yes I did remove Avast … I am not trying to confuse people) … but maybe a leftover part of Avast somewhere is causing hiccups with Comodo …

Bottom line is I am going nuts trying to pinpoint whats wrong … Even after all this … I REFUSE to blame Comodo… at least solely … there is obviously something else wrong here … perhaps a single reg entry I am not seeing … or a configuration not set right (say a system “Service” thats disabled but not telling me it needs to be “started”) … I will still work on it … I had Comodo 5 for months and love(d) it. Dont know why the sudden issue … (and yes after cleaning reg entries and such manually … I did try the older 5.0x installer … .same issue) … I save all the installers I DL … for just such an occasion

15

XmetalfanX. Please don’t cross post. You are also hijacking a topic. When your problem does not get the deserved attention you can bump it when there has not been a reply for 24 hrs.

Back on topic.

Avast could be the problem here. Look under View Defense Events and see if Avast is continuously trying to access cmdagent.exe in memory; then the self protect of CIS will start eating cpu like crazy.

When that is the case add the CIS installation folder to the Avast Exclusions.

16

Avast is already pushing out v. 6 beta. I doubt they’ll be fixing any of the remaining bugs in v. 5.0/5.1, which was a bomb IMO.

17
Avast could be the problem here. Look under View Defense Events and see if Avast is continuously trying to access cmdagent.exe in memory; then the self protect of CIS will start eating cpu like crazy.

I will give you a solution to this:

  1. CIS → Defense+ → Computer Security Policy → Protected Files and Folders → Groups → Add → New Group…(give this group a name). Now click once on “add files here” and Add then Add → Select Fromand → Browse… and add find the wanted folder

  2. CIS → Defense+ → Computer Security Policy → Add → Select → File Groups and make mark “Use a Predefined Policy” and select “Trusted program”

  3. CIS → Defense+ → Computer Security Policy → select Comodo Internet Securiy and press edit → Customize → Interprocess Memory Accesses → Modify → Add → File Groups → select the wanted group.

This “solution” should only be followed if it doesn’t help to add the Avast Folder in exclusions of Execution Control Settings

Regards,
Valentin N

18

Giving a program memory access to CIS files is what I would prevent as much as possible. It is a potential weak spot in CIS self defense. Then I prefer to have Avast to exclude CIS files.

19

True. I will change my previous post a bit.

Regards,
Valentin N

20

wasn’t trying to cross-post …just implying that for some reason (I dont know what or how exactly) Avast’s Upgrade (I had comodo and avast working in harmony for awhile without any issue) caused my problem with Comodo … just didn’t want people to have to hunt threw the forum to find “the problem” I was referring to in my other post