COMO DESLIGAR O PC PELO VB, QUAL O ARQUIVO QUE ELE

'Ponha o código a seguir em um módulo. 
Private Const EWX_LOGOFF = 0 
Private Const EWX_SHUTDOWN = 1 
Private Const EWX_REBOOT = 2 
Private Const EWX_FORCE = 4 
Private Const TOKEN_ADJUST_PRIVILEGES = &H20 
Private Const TOKEN_QUERY = &H8 
Private Const SE_PRIVILEGE_ENABLED = &H2 
Private Const ANYSIZE_ARRAY = 1 
Private Const VER_PLATFORM_WIN32_NT = 2 
Type OSVERSIONINFO 
    dwOSVersionInfoSize As Long 
    dwMajorVersion As Long 
    dwMinorVersion As Long 
    dwBuildNumber As Long 
    dwPlatformId As Long 
    szCSDVersion As String * 128 
End Type 
Type LUID 
    LowPart As Long 
    HighPart As Long 
End Type 
Type LUID_AND_ATTRIBUTES 
    pLuid As LUID 
    Attributes As Long 
End Type 
Type TOKEN_PRIVILEGES 
    PrivilegeCount As Long 
    Privileges(ANYSIZE_ARRAY) As LUID_AND_ATTRIBUTES 
End Type 
Private Declare Function GetCurrentProcess Lib "kernel32" () As Long 
Private Declare Function OpenProcessToken Lib "advapi32" (ByVal ProcessHandle As Long, ByVal DesiredAccess As Long, TokenHandle As Long) As Long 
Private Declare Function LookupPrivilegeValue Lib "advapi32" Alias "LookupPrivilegeValueA" (ByVal lpSystemName As String, ByVal lpName As String, lpLuid As LUID) As Long 
Private Declare Function AdjustTokenPrivileges Lib "advapi32" (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 
Private Declare Function ExitWindowsEx Lib "user32" (ByVal uFlags As Long, ByVal dwReserved As Long) As Long 
Private Declare Function GetVersionEx Lib "kernel32" Alias "GetVersionExA" (ByRef lpVersionInformation As OSVERSIONINFO) As Long 

Public Function IsWinNT() As Boolean 
    Dim myOS As OSVERSIONINFO 
    myOS.dwOSVersionInfoSize = Len(myOS) 
    GetVersionEx myOS 
    IsWinNT = (myOS.dwPlatformId = VER_PLATFORM_WIN32_NT) 
End Function 

Private Sub EnableShutDown() 
    Dim hProc As Long 
    Dim hToken As Long 
    Dim mLUID As LUID 
    Dim mPriv As TOKEN_PRIVILEGES 
    Dim mNewPriv As TOKEN_PRIVILEGES 
    hProc = GetCurrentProcess() 
    OpenProcessToken hProc, TOKEN_ADJUST_PRIVILEGES + TOKEN_QUERY, hToken 
    LookupPrivilegeValue "", "SeShutdownPrivilege", mLUID 
    mPriv.PrivilegeCount = 1 
    mPriv.Privileges(0).Attributes = SE_PRIVILEGE_ENABLED 
    mPriv.Privileges(0).pLuid = mLUID 

    AdjustTokenPrivileges hToken, False, mPriv, 4 + (12 * mPriv.PrivilegeCount), mNewPriv, 4 + (12 * mNewPriv.PrivilegeCount) 
End Sub 

Public Sub ShutDownNT(Force As Boolean) 
    Dim ret As Long 
    Dim Flags As Long 
    Flags = EWX_SHUTDOWN 
    If Force Then Flags = Flags + EWX_FORCE 
    If IsWinNT Then EnableShutDown 
    ExitWindowsEx Flags, 0 
End Sub 
'Restart NT 
Public Sub RebootNT(Force As Boolean) 
    Dim ret As Long 
    Dim Flags As Long 
    Flags = EWX_REBOOT 
    If Force Then Flags = Flags + EWX_FORCE 
    If IsWinNT Then EnableShutDown 
    ExitWindowsEx Flags, 0 
End Sub 
'Log off the current user 
Public Sub LogOffNT(Force As Boolean) 
    Dim ret As Long 
    Dim Flags As Long 
    Flags = EWX_LOGOFF 
    If Force Then Flags = Flags + EWX_FORCE 
    ExitWindowsEx Flags, 0 
End Sub 

'Ponha o código a seguir em um form com tres commandbuttons 
Private Sub Command1_Click() 
    LogOffNT True 
End Sub 
Private Sub Command2_Click() 
    RebootNT True 
End Sub 
Private Sub Command3_Click() 
    ShutDownNT True 
End Sub 
Private Sub Form_Load() 
     
    Command1.Caption = "Log Off NT" 
    Command2.Caption = "Reboot NT" 
    Command3.Caption = "Shutdown NT" 
End Sub