What do you want to do, disable the use of Ctrl-Alt-Del? If so, this should do the trick:
VB Code:
  1. Private Declare Function SystemParametersInfo Lib "user32" Alias _
  2. "SystemParametersInfoA" (ByVal uAction As Long, ByVal uParam As Long, _
  3. ByVal lpvParam As Any, ByVal fuWinIni As Long) As Long
  4.  
  5.  
  6. Private Sub DisableCtrlAltDelete(bDisabled As Boolean)
  7. Dim x As Long
  8. x = SystemParametersInfo(97, bDisabled, CStr(1), 0)
  9. End Sub
  10.  
  11. Private Sub Command1_Click()
  12. DisableCtrlAltDelete (False)
  13. End Sub
  14.  
  15. Private Sub Command2_Click()
  16. DisableCtrlAltDelete (True)
  17. End Sub
On the other hand, if this isn't what you want to do then give some more specifics and I'm sure we can work something out.