Codigopara apagar PC que sirva en win XP

Puedes probar con el siguiente código:
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En un modulo pega el siguiente codigo :
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Option Explicit
' Shutdown Flags
Public Const EWX_LOGOFF = 0
Public Const EWX_SHUTDOWN = 1
Public Const EWX_REBOOT = 2
Public Const EWX_FORCE = 4
Public Const ANYSIZE_ARRAY = 1
Public Const SE_PRIVILEGE_ENABLED = &H2
Public Const TokenPrivileges = 3
Public Const TOKEN_ASSIGN_PRIMARY = &H1
Public Const TOKEN_DUPLICATE = &H2
Public Const TOKEN_IMPERSONATE = &H4
Public Const TOKEN_QUERY = &H8
Public Const TOKEN_QUERY_SOURCE = &H10
Public Const TOKEN_ADJUST_PRIVILEGES = &H20
Public Const TOKEN_ADJUST_GROUPS = &H40
Public Const TOKEN_ADJUST_DEFAULT = &H80
Public Const SE_SHUTDOWN_NAME = "SeShutdownPrivilege"
Type LARGE_INTEGER
lowpart As Long
highpart As Long
End Type
Type Luid
lowpart As Long
highpart As Long
End Type
Type LUID_AND_ATTRIBUTES
'pLuid As Luid
pLuid As LARGE_INTEGER
Attributes As Long
End Type
Type TOKEN_PRIVILEGES
PrivilegeCount As Long
Privileges(ANYSIZE_ARRAY) As LUID_AND_ATTRIBUTES
End Type
'Versión para 32 bits
Declare Function ExitWindowsEx Lib "User32" (ByVal uFlags As Long, ByVal
dwReserved As Long) As Long
Declare Function InitiateSystemShutdown Lib "advapi32.dll" Alias
"InitiateSystemShutdownA" (ByVal lpMachineName As String, ByVal lpMessage As
String, ByVal dwTimeout As Long, ByVal bForceAppsClosed As Long, ByVal
bRebootAfterShutdown As Long) As Long
Declare Function OpenProcessToken Lib "advapi32.dll" (ByVal ProcessHandle As
Long, ByVal DesiredAccess As Long, TokenHandle As Long) As Long
Declare Function GetCurrentProcess Lib "kernel32" () As Long
Declare Function LookupPrivilegeValue Lib "advapi32.dll" Alias
"LookupPrivilegeValueA" (ByVal lpSystemName As String, ByVal lpName As
String, lpLuid As LARGE_INTEGER) As Long
Declare Function AdjustTokenPrivileges Lib "advapi32.dll" (ByVal TokenHandle
As Long, ByVal DisableAllPrivileges As Long, NewState As TOKEN_PRIVILEGES,
ByVal BufferLength As Long, PreviousState As TOKEN_PRIVILEGES, ReturnLength
As Long) As Long
Declare Function GetComputerName Lib "kernel32" Alias "GetComputerNameA"
(ByVal lpBuffer As String, nSize As Long) As Long
Declare Function GetLastError Lib "kernel32" () As Long
#If Win32 Then
Public Function InitiateShutdownMachine(ByVal Machine As String, _
Optional Force As Variant, Optional Restart As Variant, _
Optional AllowLocalShutdown As Variant, _
Optional Delay As Variant, _
Optional Message As Variant) As Boolean
Dim hProc As Long
Dim OldTokenStuff As TOKEN_PRIVILEGES
Dim OldTokenStuffLen As Long
Dim NewTokenStuff As TOKEN_PRIVILEGES
Dim NewTokenStuffLen As Long
Dim pSize As Long
If IsMissing(Force) Then Force = False
If IsMissing(Restart) Then Restart = True
If IsMissing(AllowLocalShutdown) Then AllowLocalShutdown = False
If IsMissing(Delay) Then Delay = 0
If IsMissing(Message) Then Message = ""
If InStr(Machine, "\\") = 1 Then
Machine = Right(Machine, Len(Machine) - 2)
End If
If (LCase(GetMyMachineName) = LCase(Machine)) Then
If AllowLocalShutdown = False Then Exit Function
If 0 = OpenProcessToken(GetCurrentProcess(), _
TOKEN_ADJUST_PRIVILEGES Or TOKEN_QUERY, hProc) Then
'MsgBox "OpenProcessToken Error: " & GetLastError()
Exit Function
End If
If 0 = LookupPrivilegeValue(vbNullString, SE_SHUTDOWN_NAME, _
OldTokenStuff.Privileges(0).pLuid) Then
'MsgBox "LookupPrivilegeValue Error: " & GetLastError()
Exit Function
End If
NewTokenStuff = OldTokenStuff
NewTokenStuff.PrivilegeCount = 1
NewToke