Разместите в модуле:
Public Declare Function
ExitWindowsEx Lib "user32" (ByVal uFlags As Long, ByVal dwReserved As
Long) As Long
Public Const EWX_LOGOFF = 0
Public Const EWX_SHUTDOWN = 1
Public Const EWX_REBOOT = 2
Public Const EWX_FORCE = 4
А это в коде:
Dim s As Long
'Так можно сделать Shut down
s = ExitWindowsEx(EWX_SHUTDOWN, 0&)
'Так можно сделать Log off
s = ExitWindowsEx(EWX_LOGOFF, 0&)
'А так Reboot
s = ExitWindowsEx(EWX_REBOOT, 0&