Enable secure logon in Windows 7

You can add an additional layer of security by enabling secure logon. Once you enable secure logon, users have to press Ctrl + Alt + Del in order to login to the computer. Perform the following steps to enable secure logon:
1. Click Start button . In the Search programs and files field, type netplwiz and press the Enter key from the keyboard (If you are prompted for an administrator password or confirmation, type the password or provide confirmation).
2. Click Advanced tab. Under Secure logon, click to place a check mark beside Require users to press Ctrl+Alt+Delete.
3. Click Apply and then click OK.