Installation of the MKS plug-in fails

On first installation of the VMware MKS plug-in using Mozilla Firefox 3.0, the plug-in appears to install however it actually is not installed.
The virtual machine console does not appear.
The following error appears in Firefox:

Error: Firefox could not install the file at https://<sm_server_hostname>/StageManager/ControlPanel/Machines/MachineDetails/ActiveXControls/xpihandler.ashx?filename=vmware-mks-windows-ff-3.xpi because: Install script not found -204

Windows

Download the MKS plug-in file from the Stage Manager server using Internet Explorer from the following address:

https://<sm_server_hostname>/StageManager/ControlPanel/Machines/MachineDetails/ActiveXControls/xpihandler.ashx?filename=vmware-mks-windows-ff-3.xpi

Where <sm_server_hostname> is your server hostname.
Rename the extension of the file from .xpi to .zip .
Unzip the file's contents into %ProgramFiles%\Mozilla Firefox\plugins .
Copy ssleay32.dll and libeay32.dll to %ProgramFiles%\Mozilla Firefox .

Download the MKS plug-in file from the Stage Manager server using wget from the following address:

https://<sm_server_hostname>/StageManager/ControlPanel/Machines/MachineDetails/ActiveXControls/xpihandler.ashx?filename=vmware-mks-linux-ff-3.xpi

Where <sm_server_hostname> is your server hostname.
Rename the extension of the file from .xpi to .zip .
Unzip the file's contents into ~/.mozilla/plugins .

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