I am trying to uninstall fixpack 29 from IHS and Plugin but getting below error, can some one help to fix resolve it?

my original version was at 7.0.0.0 and upgraded to 29, now i want to uninstall fixpack 29.

I am using uninstall response file 

below are the options:

-OPT checkFilePermissions="true"
-W backup.package="7.0.0-WS-IHS-LinuxX32-FP0000029.pak"
-W product.location="/webserver1/IBM/HTTPServer"
-W update.type="uninstall"

Failure messages are:

CWUPI0011E:
The maintenance package 7.0.0-WS-IHS-LinuxX32-FP0000029 is already installed on the system.

 

Hi srikanth,

  In base to infocenter
 
  pic.dhe.ibm.com/infocenter/wasinfo/v7r0/...
 
  Location of the maintenance package to be uninstalled

    Default directive setting
        -W backup.package=""
    Valid setting
        You must set this directive to the location of the backup file. The backup file reverses the application of the maintenance. For example, you might specify the following location on a Linux® system:

        /opt/properties/version/nif/backup/maintenance_package_to_uninstall

  You need to specify location of the backup file not the fixpack to uninstall.
 
  Hope this helps.
 
regards