Failed to initalize installer. Invalid data format

I recently uninstalled version 3 of Comodo Professional to install the latest and greatest. However, after going through ALL of the uninstall procedures, including specifically going into the registry and removing leftover keys, the message I received when attempting to install the latest and greatest version is, “FAILED TO INITIALIZE INSTALLER. INVALID DATA FORMAT.”

I have been looking through these forum’s and FAQ’s searching for someone with a similar story to tell and hopefully get an idea on what I have not done and/or considered to do. I have not found such a thread. Therefore, this thread to solicited the help of those of you who can and are willing… I thank you in advance.

hello Onlashuk

  1. Please tell me version of downloaded CIS. Will be better if you show the direct download link
  2. Go to the hosts file and print it here, please (hosts file location: “C:\Windows\System32\drivers\etc\hosts”)
  3. A log files can help me to investigate your problem. (see here:

I get the exact same error with version 7. I can’t use Comodo any more :frowning:

Wow, that’s a major kick… :wink:

Please try reinstalling CIS following Most Effective Way to Reinstall CIS to Avoid/Fix Problems by my colleague Chiron. It will provide a reliable and clean starting point.

I did all these steps and no joy. Nothing works.

Hi Sammo,
An ongoing issue?
COMODO Installer: Failed to initialize installer. Invalid data format.

You may consider the following troubleshooter.
Program Install and Uninstall Troubleshooter-Microsoft

Kind regards.

No cigar.