Shutting Down Your Computer

During a time when operating systems were less complex, it was possible to get away with just turning off your computer as soon as you were finished using it. As newer operating systems have started to make better use of the abundant memory present in modern systems, this is not the case anymore. These operating systems are designed with the assumption that you will run a short cleanup procedure prior to bringing a system down.

By not executing the shutdown procedure before turning off your computer, you may lose important data you were working on, and temporary files being used by the operating system or certain programs may be left on the hard disk, forgotten and wasting space.

Many operating systems provide a very simple way to initiate a shutdown. It's usually a matter of typing a single command or clicking a few buttons in a sequence. Therefore, you should take an extra minute to develop a habit of shutting down your computer properly.

MS-DOS and Windows 3.1x

MS-DOS by itself does not have its own specialized routine for shutting down, but you should still make sure you've closed all open programs prior to turning your computer off. This ensures no data is lost in your programs.

Exit Windows

Exit Windows dialog - This will end your Windows session.

If you are currently running Windows, you should switch to the Program Manager, click File, Exit Windows, and OK when the confirmation dialog reading "This will end your Windows session" appears.

Flush SMARTDRV Buffers

SMARTDRV is an MS-DOS tool that resides in memory, using extended memory in your computer to help speed up disk performance. Depending on how SMARTDRV is set up, you may need to run a command prior to shutting off the computer. To see how SMARTDRV is set up to run, type EDIT C:\AUTOEXEC.BAT. You can also use TYPE or EDLIN if the MS-DOS editor is not available.

Sample AUTOEXEC.BAT:

C:\DOS\SMARTDRV.EXE /X
@ECHO OFF
PROMPT $p$g
PATH C:\WINDOWS;C:\DOS
SET TEMP=C:\DOS

If you find a line in your AUTOEXEC.BAT file that executes SMARTDRV with the /X option (used by default), you don't have to do anything more prior to turning off your computer. If the /X option is missing, SMARTDRV is using write buffering. This means when you write data to your hard disk, it is first stored in memory before it is recorded to the disk in a quick burst. Write buffering promotes disk efficiency, and buffers are usually flushed automatically during system idle time. Even so, you should take care to ensure all buffers are flushed before turning off your computer.

To flush all buffers from memory to disks, type SMARTDRV /C at the prompt. You'll hear some disk activity as well as the activity light blink for a while. Once you see the next prompt appear, it is safe to turn off the computer immediately afterwards. If you do something else, you'll have to run the command again before turning off the computer, so keep that in mind.

Park the Hard Disk Heads

Since around 1989, pretty much all new hard disks are able to park their heads on their own when you turn off the computer, making them safe to transport provided they are handled carefully. If you are using a much older hard disk such as an ST-225 in an IBM AT PC or compatible clone, you may need to tell the computer yourself that the disk's heads need to be parked.

For these older disks, parking the heads is very important. As mechanical devices, these hard disks need to be able to accurately read data off of delicate magnetic platters. There is a specific region on the platters where data is not stored, and is deemed safe for heads to "park" at so any movement of the hard disk does not compromise the integrity of stored data.

The prodecure for parking the hard disk's heads varies depending on the type of system you have, or what software you've been provided to initiate the procedure. You may need to boot from a floppy disk containing a diagnostic utility used to park the heads, but if you have a special DOS program available to perform this task, it'll be more convenient to use that. You can type something like PARK at the DOS prompt before turning off the computer. If any hard disk in the system does not require manual parking, do not use a parking utility.

Even if your hard disk expects the heads to be manually parked, your computer's BIOS may be designed to automatically park them after a certain period of inactivity. IBM XT and AT PCs with a stock BIOS cannot do this, so check your computer's documentation to see if auto parking is available and if it needs to be activated by the user.

Windows 95

Windows 95 always needs to go through a shutdown routine before you can turn off the computer. The first step requires you to click on the Start button. If the Start button is not visible, move the cursor to the edge of the taskbar (usually located at the bottom) and drag up a bit to reveal the button. If the Auto hide setting is enabled, move the cursor where the taskbar is located and it will appear. If the Start button is obscured by other windows (resulting from Always on top being unset), you can just press <CTRL> + <ESC> to bring up the menu.

Windows 95 shutdown dialog

At the very bottom of the Start menu, there is an option labeled Shut Down. Click it, and a dialog will appear. You will be asked to confirm if you want to shut down the computer. Making sure the first radio option Shut down the computer is selected, click Yes and the shutdown will be initiated. You may be asked to save changes in any open programs.

Wait until the orange text reading "It is now safe to turn off your computer" appears on your screen. Once it does, you can turn off the computer. Note that some modern laptops may automatically turn off the computer for you.

If you selected Restart the computer in MS-DOS mode, it should be safe to turn off the computer as soon as you've closed out of all DOS programs besides the command prompt. You may type EXIT if you wish to return to Windows from there.

Shutting Down using a Desktop Shortcut

Here's a trick you can do if you prefer to shut down the computer another way: you can create a desktop shortcut that shuts down Windows in just one double click. This method does not ask for confirmation when you run the shortcut, so keep it around with caution.

Right click on an empty area of the desktop, move the cursor to New, then click Shortcut. You will see the Create Shortcut dialog. In the Command line box, type the following:

	RUNDLL.EXE USER.EXE,ExitWindows

When you click Next, you will be asked to give the shortcut a name. "Shut Down" is an appropriate descriptor for the shortcut, but you can use any name you want. Click Finish, and the shortcut will appear on the desktop. Whenever you double click this shortcut, Windows 95 will immediately begin its shutdown routine so you can turn off the computer afterwards.

Shut Down desktop shortcut

Windows NT

Due to Windows NT's security optimizations, how you can shut down Windows NT may vary depending on how the system or organization's policies are defined. It is entirely possible that your organization may not permit you to shut down Windows NT. Of course, this guide will assume you are running Windows NT Workstation 3.51 on a system you have sufficient control of.

Shutdown Computer dialog

There are several different ways to shut down Windows NT. One is by pressing <CTRL> + <ALT> + <DEL> and clicking Shutdown. When you click OK on the dialog that follows, Windows NT will begin its shutdown routine.

You may also exit the Program Manager, either by double clicking the button on the upper right corner or going to File > Shutdown.

Windows NT Logon dialog

Or, if you are not logged on, you may be able to shut down Windows from the logon dialog. If the Shutdown button is missing, you must log on before shutting down the computer.

Windows NT shutdown dialog - It is now safe to turn off your computer.

Once you see the dialog which reads "It is now safe to turn off your computer", you can power off the computer, or click Restart in the event you've changed your mind.

Tip: If you have permission to administer the machine, you can allow users to shut down the system using Windows NT's policy settings. Read Managing Shutdown Rights in Windows NT for details.