It's important to keep your computer as secure as possible. One way to do so is to enable secure logon so that you are required to press CTRL+ALT+DELETE to log on. Using secure logon provides an additional layer of security for your computer by ensuring that the authentic Windows logon screen appears. When secure logon is enabled, no other program (such as a virus or spyware) can intercept your user name and password as you enter it.
Click the Advanced tab, select the Require users to press Ctrl+Alt+Delete check box, and then click OK.