You can't directly.
Ctrl + Alt + Delete opens the Windows Security window if the Welcome screen
is turned off.
Turn off the Welcome screen...
1. In Control Panel, click User Accounts.
2. Click Change the way users log on or off.
3. Click to clear the Use the welcome screen for fast and easy logon check
box.
4. Click OK.
To lock a computer in a domain environment
1. Press CTRL+ALT+DELETE.
2. Click Lock Computer.
Windows displays the Computer Locked dialog box. Your system is now locked,
preventing everyone except you or a system administrator from unlocking your
system and viewing any open files or programs.
See these...
Using CTRL+ALT+DEL Key Combination to Open Windows Security Opens Task
Manager
http://support.microsoft.com/kb/281980
How to Quickly Lock Your Computer and Use Other Windows Logo Shortcut Keys
http://support.microsoft.com/kb/294317
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Hope this helps. Let us know.
Wes
MS-MVP Windows Shell/User
In
