A. While Server 2008 R2 only comes in a 64-bit version, Microsoft provides a 32-bit version of adprep, adprep32.exe, on the Server 2008 R2 media. The program is located in the Support\adprep folder, and you can use it on 32-bit DCs. Interestingly, in Windows Server 2008 the version of adprep on the 64-bit version media is actually the 32-bit version of adprep, which allows it to run on both 32-bit and 64-bit installations of Windows (the 64-bit version uses the Windows on Windows subsystem).

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