A common mistake is that you really want to install the Windows 8.1 version not the W2K12 version:
Win8.1AndW2K12R2-KB3191564-x64.msu
A common mistake is that you really want to install the Windows 8.1 version not the W2K12 version:
Win8.1AndW2K12R2-KB3191564-x64.msu