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Lock Your Computer

Because SLAC computers provide ready access to SLAC information, networks and systems, they must be protected from malicious use. It is remarkably easy to sit down at an unattended computer and access anything the previous user left up on the screen, left stored on the hard drive or can be accessed on the network—including sensitive applications like payroll. If malicious access takes place via your user account because you left your machine unattended and logged in, you can be held accountable.

What can you do to prevent this kind of abuse? The answer is simple: log out before leaving your machine or use a password-protected screen saver.

Most modern operating systems have a screen saver that can be configured to be password-protected and to automatically turn on after a certain amount of idle time. In addition, it is a good idea to manually turn on the screen saver whenever you step away from your machine. As a failsafe, you should have a password-protected screen saver configured to start within a reasonable timeout period.

For Windows: You can press the Windows key () and L keys simultaneously on most keyboards to enable the screen saver. On other keyboards you will need to press Control-Alt-Delete and select "lock computer."

For Unix: Password-protected screen savers are provided by Gnome, KDE (Linux) and CDE (Solaris) desktop environments. For other desktops you can use xscreensaver. Visit the Unix Screen Locking web page for instructions on activating and configuring these screen savers.

If you need help, please contact your departmental computing support person

In addition, effective March 14, 2008, all centrally managed Windows desktops and laptops will be configured to turn on the screen saver after 15 minutes of inactivity. Exceptions must be approved in writing by the Computer Security Officer at

Above article appeared in Mar. 13, 2008 SLAC Today.

Owner: SLAC Computer Security
Last Updated: 07/22/2010
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