Erhm.... dude, just work your way thro what switch is the right one to throw with the uninstall-string. And mind, do it on a computer with the program in question, that way you KNOW if it works or not. You got the link a few lines above to the different switches.
edit: just read that you did test it, but alas - didn't work. I must say that you missed something then.

edit: You might wanna check this out as well:

Code:
Discussion

There are two ways in which a silent uninstall can be performed.

Using a Response File

To run an uninstallation using a response file:

   1. Prepare a response file for the uninstallation (.iss) by running Setup.exe with the /r argument:

      Setup.exe /r
   2. Locate the Setup.iss file generated in the Windows folder and copy it to the desired location.

   3. Type the following at the command line (items in Italics represent data that is specific to your product's uninstallation):

      IDriver.exe /M{Your Product GUID} /s /f1"<FULLY qualified path>\YourResponseFile.iss"

Note: The /f1 parameter is necessary only if the Setup.iss file is located in a directory other than in the same location as Setup.exe.

Simple Uninstallation

If you do not want to follow the script logic and want to uninstall the product, you can use the following command line:

    IDriver.exe /M{Your Product GUID} /uninst

The /uninst parameter causes a forced uninstallation without opening the script. It rolls back the system changes made during the installation, including those from the MSI package and any InstallShield scripting.

Note: For both of these uninstallation options, the /M argument is case sensitive.

Note: By default, the file "IDriver.exe" is located in the following path:

    <ProgramFiles>\Common Files\InstallShield\Driver\<Version>\Intel 32.

link - http://support.installshield.com/kb/view.asp?articleid=Q106685

NOTE: above is more or less only valid depending on your installation, the other and previous link might still be the better and working choice. Welcome to the world of installshield.....

Edited by Björn (2007-02-02 05:17 PM)
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