[windows] batch file to check 64bit or 32bit OS

FYI, try and move away from using %PROCESSOR_ARCHITECTURE% as SCCM made a change around version 2012 which always launces Packages/Programs under a 32-bit process (it can install x64 but environment variables will appear as x86). I now use;

IF EXIST "%SystemDrive%\Program Files (x86)" GOTO X64

Jack