Const EWX_LOGOFF = 0
Const EWX_SHUTDOWN = 1
Const EWX_REBOOT = 2
Const EWX_FORCE = 4

Private Declare Function ExitWindowsEx Lib "user32" (ByVal uFlags As Long, ByVal dwReserved As Long) As Long

Private Sub Form_Load()
    msg = MsgBox("This program is going to reboot your computer. Press OK to continue or Cancel to stop.", vbCritical + vbOKCancel + 256, App.Title)
    If msg = vbCancel Then End
    'reboot the computer
    ret& = ExitWindowsEx(EWX_FORCE Or EWX_REBOOT, 0)
End Sub