How to launch a Vb script that runs in 64 bit mode from a vbscript running under Wow64

Question

I have a VB script that's being forced to run in Wow64 mode. I'd like to have it start either another script, or itself, in native 64 bit mode. Is there anyway to do that?

The initial script is being called by an explicit call to cscript.exe (not sure if this makes a difference or not)

Thanks

Answer 1

Apparently its pretty simple.

In Windows Vista and newer there is an alias folder at C:\Windows\Sysnative. If you call it it will not redirect to the c:\windows\SysWow64 32 bit folder but will force the native 64 bit executables to be called

http://msdn.microsoft.com/en-us/library/aa384187(VS.85).aspx

Therefore, you can run a vbscript in 64 bit mode from a vbscript running in wow64 mode by calling %windir%\Sysnative\cscript.exe and then providing the name of your script as a parameter.

However, this only works in Windows Vista or newer. There is a hotfix which can enable this Sysnative folder in Windows XP/2003

http://support.microsoft.com/kb/942589

Answer 2

Place the following code at the top of your script to detect if the OS is 64bit then re-run in 32bit mode

' ***************
' *** 64bit check
' ***************
' check to see if we are on 64bit OS -> re-run this script with 32bit cscript
Function RestartWithCScript32(extraargs)
Dim strCMD, iCount
strCMD = r32wShell.ExpandEnvironmentStrings("%SYSTEMROOT%") & "\SysWOW64\cscript.exe"
If NOT r32fso.FileExists(strCMD) Then strCMD = "cscript.exe" ' This probably won't work if we can't find the SysWOW64 Version
strCMD = strCMD & Chr(32) & Wscript.ScriptFullName & Chr(32)
If Wscript.Arguments.Count > 0 Then
 For iCount = 0 To WScript.Arguments.Count - 1
  if Instr(Wscript.Arguments(iCount), " ") = 0 Then ' add unspaced args
   strCMD = strCMD & " " & Wscript.Arguments(iCount) & " "
  Else
   If Instr("/-\", Left(Wscript.Arguments(iCount), 1)) > 0 Then ' quote spaced args
    If InStr(WScript.Arguments(iCount),"=") > 0 Then
     strCMD = strCMD & " " & Left(Wscript.Arguments(iCount), Instr(Wscript.Arguments(iCount), "=") ) & """" & Mid(Wscript.Arguments(iCount), Instr(Wscript.Arguments(iCount), "=") + 1) & """ "
    ElseIf Instr(WScript.Arguments(iCount),":") > 0 Then
     strCMD = strCMD & " " & Left(Wscript.Arguments(iCount), Instr(Wscript.Arguments(iCount), ":") ) & """" & Mid(Wscript.Arguments(iCount), Instr(Wscript.Arguments(iCount), ":") + 1) & """ "
    Else
     strCMD = strCMD & " """ & Wscript.Arguments(iCount) & """ "
    End If
   Else
    strCMD = strCMD & " """ & Wscript.Arguments(iCount) & """ "
   End If
  End If
 Next
End If
r32wShell.Run strCMD & " " & extraargs, 0, False
End Function

Dim r32wShell, r32env1, r32env2, r32iCount
Dim r32fso
SET r32fso = CreateObject("Scripting.FileSystemObject")
Set r32wShell = WScript.CreateObject("WScript.Shell")
r32env1 = r32wShell.ExpandEnvironmentStrings("%PROCESSOR_ARCHITECTURE%")
If r32env1 <> "x86" Then
 ' we are not running in x86 mode, so run in that mode; check if we have done this already
 For r32iCount = 0 To WScript.Arguments.Count - 1
  r32env2 = r32env2 & WScript.Arguments(r32iCount) & VbCrLf
 Next
 ' MsgBox "64bit (restarting) " & r32env2
 If InStr(r32env2,"restart32") = 0 Then RestartWithCScript32 "restart32" Else MsgBox "Cannot find 32bit version of cscript.exe or unknown OS type " & r32env1
 Set r32wShell = Nothing
 WScript.Quit
Else
 For r32iCount = 0 To WScript.Arguments.Count - 1
  r32env2 = r32env2 & WScript.Arguments(r32iCount) & VbCrLf
 Next
' MsgBox "32bit! " & r32env2
End If
'MsgBox "OS: " & r32env1 & VbCrLf & "Param: " & r32env2 & VbCrLf & "Script: " & WScript.FullName & VbCrLf & "Fullname: " & " " & Wscript.ScriptFullName
Set r32wShell = Nothing
Set r32fso = Nothing
' WScript.Quit
' *******************
' *** END 64bit check
' *******************