Exiting Windows Gracefully | Special Edition Using Microsoft Windows XP Professional (3rd Edition)

When you've finished a Windows XP session, you should properly shut down or log off to ensure that your work is saved and that no damage is done to the operating system. Shall we reiterate? Shutting down properly is very important. You can lose your work or otherwise foul up Windows settings if you don't shut down before turning off your computer. If multiple people share the computer, you should at least log off when you're finished so that others can log on. Logging off protects your work and settings from prying eyes. When you shut down, Windows does some housekeeping, closes all open files, prompts you to save any unsaved work files, and alerts the network that you and your shared resources are no longer available for consultation.

There are several ways to shut down the computer, all or only some of which might apply to your machine. Newer machines will have more shutdown features because they're likely to have advanced power management built into them via ACPI.

Here are the steps for correctly exiting Windows:

Close any programs that you have running. (This can almost always be done from each program's File, Exit menu or by clicking the program's close button.) If you forget to close programs before issuing the Logout or Shut Down command, Windows will attempt to close them for you. If you haven't saved your work, you'll typically be prompted to do so. Some programs, such as DOS programs, you'll have to manually close. Windows will alert you if it can't automatically close an open program. Quit the DOS program and type exit at the DOS prompt, if necessary. If you are just switching user context, your open application's status is saved so you can quickly return to it later.

Click Start, Turn Off Computer. You'll see the dialog box shown in Figure 4.16.

Figure 4.16. The Turn off computer selection dialog box.

Click on the desired option.

Here are some points to consider:

The Hibernate option records the current state of the system to disk, and then shuts down the computer. Once the power is turned back on, the system reboots. If you log back in as the same user who initiated the hibernation, the system returns to its exact state at the moment of hibernation.
If your computer has Advanced Power Manager (APM) or Advanced Configuration and Power Interface (ACPI) built in, you will see the Standby option instead of Hibernate. (Standby is explained later in this section.) This will certainly be the case with PCs fitted with ATX motherboards (as opposed to the older AT-style PC) and power supplies. The ATX motherboards have standby capability that Windows XP should recognize and utilize. If your system isn't ACPI enabled, you won't see the Standby option.
If you have an APM or ACPI system and want to Hibernate your system rather than put it on Standby, you can access this option by pressing and holding Shift. This action changes the Standby button to Hibernate. Be sure to hold the Shift key down while you click the Hibernate button.
If you want to log off, use the Log Off command button from the Start menu instead of the Turn Off Computer command button (first click Cancel on the Turn Off Computer dialog box). There are no logoff options offered in the Turn Off Computer dialog box.
If you attempt to shut down the computer while another user's desktop is still active (that is, Switch User was employed and at least one other user is still logged on), you'll see a warning message stating that performing a shutdown could result in data loss along with the options to continue with shutdown (Yes) or abort (No).

TIP

Logging off clears personal settings from memory and puts the computer in a neutral state, waiting for another user to log on. However, it doesn't bring the system to its knees. Logging off will not stop running services, which can include Web services, file sharing, print sharing, UPS support, and scheduled tasks. When the Log Off command button is clicked on the Start menu, you are offered two options: Switch User or Log Off. The latter exits you from the system and closes all applications. The former retains your environment while allowing another user to gain access to their desktop.

Standby puts the computer in a suspended state, letting you quickly come right back to where you were working before you suspended the PC. This means you don't have to exit all your applications before turning off your computer. You only have to choose Standby. This also saves energy, because the hard drives, CPU, CPU fan, some internal electronics, and possibly the power supply and fan will go into a low-power state. Your monitor, if Energy Star compliant, should also go into a frugal state of energy consumption. When you want to start up again, a quick press of the power switch (on some computers a keypress on the keyboard or a jiggle of the mouse will do) should start up the system right where you left off. Make sure to press the power button for just a second or so. Anything more than four seconds on most modern computers in a standby state will cause the computer to completely power down.

Be aware that Standby will hold your system state only so long as the computer has power. If the power fails, everything stored in the computer's RAM will be lost. You'll end up doing a cold boot when the power is restored or, if it's a laptop with a dead battery, when you hook your AC adapter up to your laptop again. The moral is to be cautious when using Standby. You should save your work before going into Standby mode, if not close important documents.

One of the most welcome features of recent versions of Windows, including Windows XP, is hibernation. Like Standby mode, hibernation lets you pause your work and resume later, without laboriously shutting down and reopening all your applications and files. But unlike Standby, Hibernate isn't volatile. If the AC power fails or batteries run flat, it doesn't matter because Hibernate stores the "system state" on a portion of the hard disk rather than keeping the system RAM alive in a low-power state. After storing the system state to the hard disk, the computer fully shuts down. When restarted, a little internal flag tells the boot loader that the system has been stored on disk, and it's reloaded into memory.

Hibernation requires as much free hard disk space as you have RAM in your PC. If you have 512MB of RAM, you'll need 512MB of free disk space for hibernation to work. If Hibernate is not an option on your Shut Down menu, enable it through the Power Options in Control Panel. The dialog box reports the amount of disk space needed for your system in case you're unaware of the amount of RAM in your system.

When you choose Hibernate from the shutdown menu, Windows XP has to create a fairly large file on disk. In my case, for example, it's 2GB in size. On a 3GHz Intel Pentium 4, the entire process takes about 15 seconds. Restarting takes about the same amount of time. Remember, if you're going to put a laptop running on batteries to sleep for more than a few hours, use Hibernate or just do a complete shutdown, closing your applications and documents. That way, if the batteries run out, you won't lose your work.