Group policy preferences that only target 32bit or 64bit os

The WMI Filter method is the best one to use because it's defined seperately of the GPO, natively administered in the GPMC, and can be linked to one or more GPOs as required.

Target 32-bit OS's with:

• Namespace: root\CIMv2
• Query: Select * from Win32_Processor where AddressWidth = '32'

Target 64-bit OS's with:

• Namespace: root\CIMv2
• Query: Select * from Win32_Processor where AddressWidth = '64'

In my experience if there is an issue with WMI on the system it can not run the query. If you are using Windows 2008 preferences then I would use a environment variable for the Group Policy item-level targeting filter.

For x64 the environment variable %Processor_Architecture% is AMD64

For x86 the environment variable %Processor_Architecture% is x86

Environment variables are much more stable than WMI