Win32 provides no direct method for disabling task-switching functions.
They are, however, disabled whenever the screen saver is active in order to
provide for password-protected savers. This can be exploited under Windows
95 by using API calls to declare the current application to be an active
screen saver. The actual screen saver will not start while this is in
effect. This also does not function under Windows NT.

Private Declare Function SystemParametersInfo Lib "user32" _
Alias "SystemParametersInfoA" (ByVal uAction As Long, _
ByVal uParam As Long, lpvParam As Any, _
ByVal fuWinIni As Long) As Long
Private Const SPI_SCREENSAVERRUNNING = 97

Private Sub cmdDisable_Click()
SystemParametersInfo SPI_SCREENSAVERRUNNING, True, ByVal 1&, 0
End Sub

Private Sub cmdEnable_Click()
SystemParametersInfo SPI_SCREENSAVERRUNNING, False, ByVal 1&, 0
End Sub

Private Sub Form_Unload(Cancel As Integer)
' re-enable Ctrl+Alt+Del and Alt+Tab before the program terminates!
cmdEnable_Click
End Sub

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