Cannot Install Siebel Tools or Siebel Client : "Class Not Registered"

Issue

When you click on "Install.exe" for a Siebel Mobile Web Client or Siebel Tools installation, after selecting the desired language, you get the following error message in a popup window:

"An error occured while launching the setup" - "Class not registered"

Cause

The fact that the installer fails at the very beginning after clicking on "Install.exe" indicates this could be an external issue related to the InstallShield software used by Siebel to install the Siebel application.

Further investigation revealed that the "Engine" folder was missing under "C:\Program Files\Common Files\InstallShield". This engine folder is required by InstallShield.

As per InstallShield web site: "Sometimes in an attempt to fix installation-related errors, you may have to update the engine that runs the installation itself"

Solution

1. Launch Windows Explorer by pressing Windows Key + E on your keyboard or select Start > Run and type explorer.
2. Browse to C:\Program Files \Common Files\InstallShield\engine. (This folder was missing)
3. Right-click the highlighted engine directory and select Delete.
4. Install the latest version of the iKernel engine.

1. Download iKernel engine update and save it to your Desktop. (http://support.installshield.com/kb/files/Q108312/ikernelupdate.exe)

2. Double-click on ikernelupdate.exe to install.

After re installing the kernel try to install to0ls/client again this time you will be able to do so.