IgNiTeD SoUL

The /32 and /64 parameters for the mmc command are meaningful only on 64-bit Windows versions. The 64-bit versions of the Windows operating system can run both 32-bit and 64-bit versions of the MMC. For 32-bit versions of the MMC, you use 32-bit snap-ins. For 64-bit versions of the MMC, you use 64-bit snap-ins. You can’t mix and match MMC and snap-in versions, though. The 32-bit version of the MMC can be used only to work with 32-bit snap-ins. Similarly, the 64-bit version of the MMC can be used only to work with 64-bit snap-ins. In most cases, if you aren’t sure which version to use, don’t use the /32 or /64 parameter. This lets the Windows operating system decide which version to use based on the snap-ins contained in the .msc file you are opening.

When a console contains both 32-bit and 64-bit snap-ins and you don’t specify the /32 or /64 parameter, Windows will open a subset of the configured snap-ins. If the console contains more 32-bit snap-ins, Windows will open the 32-bit snap-ins. If the console contains more 64-bit snap-ins, Windows will open the 64-bit snap-ins. If you explicitly use /32 or /64 with a console that contains both 32-bit and 64-bit snap-ins, Windows will open only the snap-ins for that bitness. On 64-bit systems, 32-bit versions of snap-ins are stored in the %SystemRoot%\SysVoL64 folder and 64-bit versions of snap-ins are stored in the %SystemRoot%\System32 folder. By examining the contents of these folders, you can determine when 32-bit and 64-bit versions of snap-ins are available.