Comodo Antivirus Refuses to Update or Scan

I just tried to install Comodo Antivirus on my Uncle’s laptop. After the installation completed, I noticed that the database version was 0. After some research I figured out that I had to manually download and install the virus definitions myself (why??). Since it has been installed until now, it still refuses to update at all, resulting in instant errors. It also will not do a scan, as it tries to update before scanning. If It was up to me, I would have Avast! running on his machine anyway, but he insists that Comodo be installed. Could someone please help me figure this problem out so that I can give him back his laptop?

Hi and welcome fox091,
Please try a re-install following the instructions in the link below.
Most Effective Way to Reinstall/Update CIS to Avoid/Fix Problems
Also before re-installing, please run the corresponding uninstaller tool for any previously installed security software.
Uninstallers (removal tools) for common Windows antivirus software-ESET Knowledgebase

Thank you.

I will try these steps tomorrow as I am about to go to bed. I will report back with results.

I also have a problem with the AV update
I re-install two times following the instructions, nothing :frowning:
I always get the following message
Errore: 0x80072efd - Impossibile stabilire una connessione con il server

Windows 8.1 pro, latest version of CIS.

I have followed those steps and ran the uninstallers for any other AV programs that were present on the machine. I have since reinstalled Comodo Antivirus and it is doing the exact same nonsense. I am going to embed/attach some images of what exactly is happening. I have not yet manually installed virus definitions yet.

I am sorry I do not know why this is occurring, let us hope someone else has some suggestions or help to shed some light on the issue.
It maybe worth considering creating a bug report.
Bug Reports - CIS
Required Format For Reporting Bugs

Thank you.

I have the exactly same problem, except that it happened for me after a week where I didnt boot my computer at all. When I started my computer, Windows (7) told me that the virus database needed to be renewed, and then the bug was there: No connection to the server. I uninstalled Comodo and reinstalled it 3 times, with no luck so far… Any suggestions?
Thank you for your help, and let me tell you that I have used Comodo for 5 years now, and this is the very first time I experience such a serious bug… :-[

Hi and welcome Maroan,
In case the Database file is corrupt you could try the following.
Note: If successful this will download the entire Database file (Est 236 MB).

  1. Rename the bxxxxx.cav file to bxxxxxold.cav.
  2. Manually check for DB updates and allow the DB file to be downloaded and installed.
  3. Delete the bxxxxxold.cav file. (Reboot maybe required to allow deletion).
    File found at the following location,
    C:\Program Files\COMODO\COMODO Internet Security\scanners

If the above fails, you could try downloading the Database file and manually importing it.
Anti-Malware Database-Comodo
Title bar controls-Comodo Help
Kind regards

Kind regards.

Well Ive tryed your advice and it didnt help. I manually downloaded allready for 2 days ago a new virus database (19130) and today, following your advice, I did the same. It seems to work, but when I check the database version, its still the version 19130. And now Comodo warns me that the database is outdated…
My Comodo version is 7.0.317799.4142, running on Windows 7 Ultimate 64 bits.

Should I uninstall (Again) and do a fresh installation?
And again, thanks for helping!

iv got the same issue ever since latest update my cis has refused to update or scan properly iv uninstalled it and reinstalled it even imported the the virus def and still hasent fixed the problem

for info:

i cant read french

Does the following solution help in your case:;msg769911#msg769911 ?

You can also check with malwarebytes or hitmanpro or both, for leftovers or infection that you did not notice previous, just in case.

There is also the hosts file connection which is altered very usual by malware or is being corrupted