• Even though a computer that is turned off will save energy, it then cannot be backed up or updated.
• The principles below apply to any operating systems.
  • Most of the specific instructions below are geared towards Windows computers, but similar capabilities are available on Macs, too.

Recommendation for temporarily leaving your computer (during your work day)

Save your work.

• This protects you from a power glitch turning off your computer.
• Also, saving your work ensures anyone needing to work on the computer doesn't have to guess if there is any unsaved work.

Lock your computer so others can't use it with your account.

• Set your computer to auto-lock after a set amount of inactivity.
  • http://www.it.cornell.edu/security/howto/screenlockhowwin.cfm
  • http://www.it.cornell.edu/security/howto/screenlockhowmac.cfm
  • http://support.apple.com/kb/PH13943
• Lock your computer when you leave it by pressing the Windows key and the "L" key (Windows)

Cornell's IT Security Policy 5.10 (p.16), within the "Baseline Requirements for All Computers" section, states:

• 5. For any computer system that is not in a secure, private space, run a password-protected screen saver, or some other console-locking mechanism, that is triggered after fifteen minutes (or less) of inactivity.

Note: ChemIT/ PhysIT can assist you with setting your computer to auto-lock. (At some point, we would like to offer this as a default setting on Admin systems, invoking the screensaver lock after, say, 15 minutes, with preference managed for both a Windows and MacOS computers.)

Recommendation for leaving your computer for the night

Log off of your computer so its files can be backed up completely.and it can safely be rebooted as part of updating.

• Logging off requires that you have saved your work, and it:
  • reduces the chance of a problem resulting from a power glitch and the like.
  • ensures anyone needing to work on your computer doesn't have to guess if there is any unsaved work, especially if they must reboot it.
  • allows your computer to get patches applied and reboot automatically, returning it to the log-in screen you left it at without interrupting your work when you are at work.
• Logging off also reduces the risk your desktop icons will shift if you have to remote to your computer (applicable only to a few staff who must work from home).
  • You can technically remote in to your system when it is not logged off, but doing so can lead to surprises in how your desktop icons are arranged, due to different display resolutions.

Recommendation for leaving your computer for more than one night, such as a weekend or holiday

Turn off your computer if you won't need to use your computer for more than one night. Save energy. And any power glitches will obviously not shut down your computer inelegantly. :-)

Also, a turned off computer ensures anyone needing to work on your computer doesn't have to guess if there is any unsaved work, same as if it is logged off.

Note: If you must access your computer remotely, and have permission to do so, you must leave it on.