The update file is not valid...

I'm trying to update the installation file which is a requirement to install on 2012 server following the steps described on :blogs.msdn.com/.../installing-crm-2011-on-windows-server-2012.aspx

But  I'm getting the error :

10:16:16|  Error| File "C:\Install\Update\Server_KB2434455_amd64_1033.msp" is not a Windows Installer Update file. (packagevalidator.cpp:CWindowsInstallerPatchPackageValidator::Validate:334).

10:16:16|   Info| Expected parameters for update file:

Upgrade code - {20EA1269-CD24-459C-B8D7-E227D70386D9}

Product code - {0C524D55-1409-0050-BD7E-530E52560E52}

ProductLanguage - 1033

BaseVersion - 5.0.9690.1992

10:16:16|  Error| The update file is not valid for installation of this application.

I tried to extract the cab on my desktop and on the server but without any success.

any ideas ?

Best Regards

Tomaz