Running 64bit from a 32bit environment

As we know, there’s a little feature in 64 bit windows that auto redirects 32 bit apps to 32 bit versions of system files via the WOW64 file system redirector. This causes some issues when deploying apps via things like older versions of Altiris NS to 64 bit Operating Systems.

This can be overridden via a little known feature called sysnative. Using this special alias will tell windows not to redirect to 32bit system files, ie we can run windows installers in 64 bit mode by launching it from a 64 bit cmd line launched from the 32 bit Altiris Agent environment:

%windir%/Sysnative

NOTE: If you try to use sysnative in a 64 bit cmd line it will fail as it is a virtual directory in the 32bit environment, not the real one.

http://msdn.microsoft.com/en-us/library/windows/desktop/aa384187(v=vs.85).aspx

How to test:

On 64 bit OS, run

C:Windows\SysWOW64\cmd.exe

run ‘set’ and check PROCESSOR_ARCHITECTURE = x86 (32bit)

cd %windir%sysnative

run ‘cmd.exe’

run ‘set’ and check PROCESSOR_ARCHITECTURE = AMD64 (64bit from a 32bit command line!!)

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