cis.exe not opening

I have no problem installing, but I don’t see any other support subforum so here’s my problem (move to correct subforum is there is)

My comodo is running, with the widget and the icon on the tray. However, when I double-click on it, or right-click Open, the interface does not show up.

I checked the Task Manager, and cis.exe shows up for a bit and quickly closes. Any idea what could have happened?

Hi and welcome dragonjet,
What is your operating system?
What CIS version?
Do you have any other security software installed?
Did this only recently start occurring?
Was it a clean install or an update of CIS?


Windows 7

I installed it from the latest installer I downloaded from the website. I don’t know the version though, doesn’t say in the installer filename, there’s no “About” on the right-click menu of systray, and I wanna look at version number on the main interface but as mentioned I cannot open it XD

This is actually not the first time it happened. I had CIS for a long time, and probably last month I got this problem (CIS main interface not opening). So I uninstalled it. When I get weary of security again I tried to install it again, and here I am.

I have never used any other anti-virus software though.

Thanks in advance~

Hi dragonjet,
This is a strange occurrence.
If you navigate to the following folder and hover over the ‘cis.exe’ file this will tell the version number.
C:\Program Files\COMODO\COMODO Internet Security
Does double clicking the mentioned file open the GUI?
Or can you open the GUI from Windows start menu?


checked the file properties, it’s version

After reinstalling a few times, it now gives me “Engine initialization failure”.

Previously there’s no popup like this when I’m trying to open the GUI

Hi dragonjet,
Sorry this issue is persistent, about the only thing I can suggest is trying the instructions in the link below with the new version that is available.
Most Effective Way to Reinstall/Update CIS to Avoid/Fix Problems
Comodo Internet Security (with Win10 Support) is released!!

Thanks for your patience and determination.

Edit: Does the system CPU have SSE2 support, it is a requirement since version 8.2.

Thanks for the responses, but is there any official article/blog/post that I can read as to why this happens to latest versions?

Personally I was satisfied with CIS for many years now, and now this

I really don’t think that community workarounds and tools are ideal for this situation. It nearly killed my computer and affected my Git software, the one I use for work and that System Restore did not help. I fixed the git now but I’m not sure if there are any remnants of the CIS failure on my computer.

The developers should push a patch to the software that will really fix it. As it is right now, it really not ideal.

Hi dragonjet,
I do not know of any documentation on why this would occur.
This is not a common issue and could be hard to reproduce which in turn will make it difficult for Developers to resolve.
For this reason, I suggest creating a bug report which could assist the Developers.
Bug Reports - CIS
Required Format For Reporting Bugs