Issue:  

Upgrade or uninstallation of Forefront Client Security (FCS) v1 is not possible, after an in place upgrade of Windows Server 2008 Core to Windows Server 2008 R2 Core.

 

Cause: 

The Antimalware MSI’s used to install the AM engine for FCS use an application installer known as DFXAPP.   The version of the installer used in the original FCS media and in subsequent updates to the AM MSI (QFE2, QFE4, QFE5, QFE6) has a hard coded version block that prevents this installer from running on Windows 7 and Windows Server 2008 R2.    In most cases, there is an application compatibility ‘shim ‘ that works around this issue and allows the installation to succeed.   However, this application compatibility infrastructure is not installed or supported on Windows Server 2008 R2 Core  - and an installation error happens.

 

The scenario of concern is if:

 

·         A customer has already installed FCSv1 on Windows Server 2008 Core;

·         Then upgrades the operating system to Windows Server 2008 R2 Core,

 

The following is the result:

 

·         You cannot uninstall FCSv1.  (due to the lack of the DFXAPP infrastructure)

·         You cannot upgrade the Antimalware QFE to future release.   This because the upgrade occurs by performing an uninstall of the current Antimalware QFE. (again due to the lack of the DFXAPP infrastructure)

 

 

The specific error seen in the Antimalware log (FCSAM.log):

 

MSI (s) (CC:E0) [20:43:51:595]: Invoking remote custom action. DLL: C:\Windows\Installer\MSI18B5.tmp, Entrypoint: ProcessDriverPackages Action start 20:43:51: MsiProcessDrivers.

DIFXAPP: ENTER: ProcessDriverPackages()

DIFXAPP: ERROR - The operating system you are running on is not supported. Only Windows 2000, Windows XP, Windows Server 2003 and Windows codenamed Longhorn are supported.

 

Solution:

There are several workarounds that exist, but are very time consuming and error prone.   We are working to create a simpler workaround that can be distributed to affected customers.  If you find yourself in this situation, please open a case with your CSS representative via http://support.microsoft.com