You are running an x64-based version of Windows Vista or of Windows Server 2008 on a computer that has multiple Intel x64 processors or has an Intel x64 multi-core processor. When you try to install Windows Vista Service Pack 2 or Windows Server 2008 Service Pack 2 on the computer, you receive the following Stop error message:

Stop 0×0000003E (parameter1, parameter2, parameter3, parameter4)
MultiProcessor_Configuration_Not_Supported

Note When this problem occurs, parameter1 and parameter2 in this Stop error message can make the following equation valid:

((parameter1 ^ paramater2) & (0×00100000))!= 0