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Comodo Internet Security Installation Error 1603

I have been using Comodo Internet Security since it’s initial release and it just keeps getting better and better. However whilst trying to install the most recent version 4.0 which was released on March 03 2010 I encountered an installation error 1603. Naturally I cleared all the junk files, disabled unnecessary services, cleared the registry and still couldn’t get it to work until I came across a handy clean up tool which cleans up leftover data from the previous installations.


Version 4 is a major update so you will need to uninstall any previous versions that exist on your computer. I am assuming that you have already attempted installing the software and have it situated in a folder on your system.

Step 1- Download and Extract Software- Updated 6th September!

There are 2 versions of the Comodo Clean up tool. I suggest that you try the original version first and if that fails use version 2 . Both versions are spyware and virus free.
Extract the file using 7zip or similar. You should now have a folder called CIS Clean-up Tool.

CIS Clean Tool

Step 2-Run File and re-install CIS4

Navigate to CIS Clean-up Tool folder and run the CIS File+Registry Cleaner.bat file. Vista and 7 users need to right click and select run as administrator. Follow the on-screen prompts. This file will clean all associated registry entries, files and folders that have been left over from previous installations.

MS-Dos batch file

To re-install CIS4 navigate to the download folder:

Windows XP C:/Documents and Settings/All Users/Application Data/Comodo Downloader and run CIS_Setup.msi
I am not currently running Vista or 7 so I am unsure where the default download folder is situated.

Your installation should now run smoothly. I would like to thank Ragwing for creating this script. If you have any questions or neither of the above tools work then please feel free to comment below or contact me through my contact form.

47 replies on “Comodo Internet Security Installation Error 1603”

Avatar of Nick

Struggled for the last 2 days on and off to get Comodo to update. Followed your instructions and it worked straight away. Absolutely brilliant, thank you very much.

Avatar of Tracy Ridge

@John I can only suggest that you manually look for any files or registry entries that contain comodo and delete them. It is very frustrating and you would think that it would have been addressed by now, especially as it is an ongoing problem.

Avatar of Oompa Loompa
Oompa Loompa
Oompa Loompa On

I was skeptical… but thank you … your tool and tips removed my roadblock of the error 1603 when installing….

Thanks again

Avatar of John Mihaljevic
John Mihaljevic
John Mihaljevic On

Have run the CIS Clean-up Toolas per your instructions, but CIS still fails to install.
I have Windows XP Home SP 3.

Avatar of Rakulus

Thank you!!! Had old Comodo Firewall and Avast antivirus and was trying to update. This fixed the install error!

Avatar of Anonymous
Anonymous On

The following lines in the batch script have typos:

CurrentVersion\Explorer\Browser Help Objects\{F0D4B231-DA4B-4daf-81E4-DFEE4931A4AA}” /F

CurrentVersion\Explorer\Browser Help Objects\{201f27d4-3704-41d6-89c1-aa35e39143ed}” /F

They should read “Browser Helper Objects” on Windows XP.

Avatar of Davie

Many thanks for this, I was getting the Error 1603 until running the clean-up tool. Installed no problem after use!

Avatar of A guy out his mind because fxxing COMODO 4
A guy out his mind because fxxing COMODO 4
A guy out his mind because fxxing COMODO 4 On

i think i still can’t install COMODO 4 forever

fxxking 1603 error appear again and again even using this CIS Clean-up Tool

WTF COMODO you want to tell me i need FORMAT MY HARD DRIVE?!

I would rather use COMODO 3 than use COMODO 4

Avatar of Richard

Thanks for publishing this. It doesn’t say much for Comodo that this has been a problem since March and they haven’t fixed it yet. What about the non-techies out there that won’t have a clue about finding a solution.

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