How to detect if the computer is 32-bit or 64-bit?

How do you determine if the computer you are on is a 32-bit m开发者_开发问答achine or a 64-bit machine?

I need this done in vba preferrably.

@Wouter Simon's answer is sort of on the right track, but really incomplete. It is missing a couple of Declare statements as well as some kind of explanation.

Therefore I believe it's worth presenting a more complete and working version here.

Private Declare Function GetProcAddress Lib "kernel32" _
    (ByVal hModule As Long, _
    ByVal lpProcName As String) As Long

Private Declare Function GetModuleHandle Lib "kernel32" _
    Alias "GetModuleHandleA" (ByVal lpModuleName As String) As Long '()

Private Declare Function GetCurrentProcess Lib "kernel32" () As Long

Private Declare Function IsWow64Process Lib "kernel32" _
    (ByVal hProcess As Long, ByRef Wow64Process As Long) As Long

Sub CheckWhetherIts64()

    Dim Its64 As Long
    Dim handle As Long

    handle = GetProcAddress(GetModuleHandle("kernel32"), _
                   "IsWow64Process")

    If handle > 0 Then ' IsWow64Process function exists
        ' Now use the function to determine if
        ' we are running under Wow64

        IsWow64Process GetCurrentProcess(), Its64
    End If
    If Its64 = 1 Then
        MsgBox "it's a 64 bit process."
    End If
End Sub

Caveat:

For compatibility with operating systems that do not support this function, call GetProcAddress to detect whether IsWow64Process is implemented in Kernel32.dll. If GetProcAddress succeeds, it is safe to call this function. Otherwise, WOW64 is not present. Note that this technique is not a reliable way to detect whether the operating system is a 64-bit version of Windows because the Kernel32.dll in current versions of 32-bit Windows also contains this function.

http://msdn.microsoft.com/en-us/library/ms684139%28v=vs.85%29.aspx

got it from http://www.msoffice.us/Access/PDF/Extending%20VBA%20with%20APIs.pdf. Seems like it is working on mine.

Option Compare Database

Type SYSTEM_INFO
wProcessorArchitecture As Integer
wReserved As Integer
dwPageSize As Long
lpMinimumApplicationAddress As Long
lpMaximumApplicationAddress As Long
dwActiveProcessorMask As Long
dwNumberOrfProcessors As Long
dwProcessorType As Long
dwAllocationGranularity As Long
wProcessorLevel As Integer
wProcessorRevision As Integer
End Type

Declare Sub GetNativeSystemInfo Lib "kernel32" (lpSystemInfo As SYSTEM_INFO)
Declare Function GetCurrentProcess Lib "kernel32" () As Long

Public Function Is64BitProcessor() As Boolean
Const PROCESSOR_ARCHITECTURE_AMD64 As Integer = 9
Const PROCESSOR_ARCHITECTURE_IA64 As Integer = 6
Dim si As SYSTEM_INFO
' call the API
GetNativeSystemInfo si
' check the struct
Is64BitProcessor = (si.wProcessorArchitecture = PROCESSOR_ARCHITECTURE_AMD64 _
Or _
si.wProcessorArchitecture = PROCESSOR_ARCHITECTURE_IA64)
End Function

http://msdn.microsoft.com/en-us/library/ms724340(v=vs.85).aspx

To determine whether the running Office is 64-bit or 32-bit: Use IsWow64Process (answer from Jean-François Corbett).

To determine whether Windows is 64-bit or 32-bit:

Public Function isWin64bit() As Boolean
  isWin64bit = 0 < Len(Environ("ProgramW6432"))
End Function

I think the most straightforward way is:

#If Win64 Then
    MsgBox "Win 64"
#Else
    MsgBox "Win 32"
#End If

Sometimes it is also useful to check whether your Office is 32 or 64 and use this information to access the correct key in registry. So you can do:

#If Win64 Then
    #If VBA7 Then
        MsgBox "Win 64 and Office 64" ' HKEY_LOCAL_MACHINE\SOFTWARE\YourApp
    #Else
        MsgBox "Win 64 and Office 32" ' HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\YourApp
    #End If
#Else
    MsgBox "Win 32 and Office 32" ' HKEY_LOCAL_MACHINE\SOFTWARE\YourApp
#End If

HTH

Conditional compilation could be very useful, WinXX detects environment but not hardware properties, example below :

   Dim mVers   As String

Sub Init()

    #If Win64 Then
        mVers = "Win64" ' Win64=true, Win32=true, Win16= false
        Call VerCheck
    #ElseIf win32 Then
        mVers = "Win32"  ' Win32=true, Win16=false
        Call VerCheck
    #ElseIf win16 Then
        mVers = "Win16"  ' Win16=true
        Call VerCheck
    #End If

End Sub

Sub VerCheck()
    MsgBox "Version: " & mVers, vbInformation, "Version"
End Sub

I think VBA may be linked to the office version that is running and it really matters what type of process is running. This code snippet may help (VB6 code)

Private Declare Function GetProcAddress Lib "kernel32" _
    (ByVal hModule As Long, _
    ByVal lpProcName As String) As Long

Private Declare Function GetModuleHandle Lib "kernel32" _
    Alias "GetModuleHandleA" _

handle = GetProcAddress(GetModuleHandle("kernel32"), _
               "IsWow64Process")

If handle > 0 Then ' IsWow64Process function exists
    ' Now use the function to determine if 
    ' we are running under Wow64
    IsWow64Process GetCurrentProcess(), bolFunc
End If