c# - Block Control+Alt+Delete

Question

I am doing an Online Quiz project in C#. The test client is a Windows Desktop Application running on Windows XP. I need to block the control+alt+delete key combination to prevent students from minimizing/closing the application.

Using PInvoke is okay for me.

I know this is definitely possible because I have seen three applications doing this. They are all proprietary, so I have no way of knowing how it was done.

Answer 1

I found a very ugly way of doing this (which works well). If I open taskmgr.exe exclusively, then nothing happens when the user presses Ctrl+Alt+Del.

FileStream fs = new FileStream(System.IO.Path.Combine(Environment.SystemDirectory, "taskmgr.exe"), FileMode.Open, FileAccess.ReadWrite, FileShare.None);

What I like the most about this solution that it has no permanent effects. For example if the application gets killed, then Ctrl+Alt+Del will just work again.

Drawback: One must have the Welcome screen enabled or Windows Security will popup instead of Windows trying to open taskmgr and silently failing. (→ It also won't work if the machine is in a domain, because being in a domain disables the Welcome screen.)

(Of course this won't work on Vista or W7.)