Absolute Beginners Guide to Upgrading and Fixing Your PC

There's one more Windows utility that can prove useful when you're trying to fix problems with your system even though using it improperly can cause unpredictable behavior on the part of your PC. This utility is called the Registry Editor, and you use it to change key system settings in the Windows Registry.

The Windows Registry is a huge database that holds the majority of your system's configuration information. The Registry contains all the properties you set via the Control Panel, settings for each of the applications installed on your system, and configuration information for all your system's hardware and peripherals.

The Registry is updated automatically whenever you change a configuration through normal means. You also can make changes directly to the Registry, using the Registry Editor.

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Backing Up and Restoring the Registry

Because editing the Registry is risky even for experienced computer users you should back up the Registry files before you commence making any changes. This will give you the option of restoring the pre-edited Registry, just in case anything goes wrong.

Fortunately, the System Restore utility automatically backs up your Registry whenever a restore point is created. If you're going to edit your Registry, be sure you create a new restore point immediately prior to making any changes. If anything goes wrong in the editing process, you can use System Restore to restore your system back to the previous restore point.

If you're using a version of Windows prior to Windows Me (which first introduced the System Restore feature), or if you just want to be extra safe, you can make a backup copy of your Registry and store it on some form of removable media, such as a Zip disk or CD-R/RW. The Registry is actually composed of two hidden files, SYSTEM.DAT and USER.DAT, located in the \windows folder. All you have to do is unhide these files and copy them to another location. That way you can copy them back later if you end up totally trashing your system with the Registry Editor.

Editing the Registry

Most of the time you won't need to bother with the Registry. However, there will come the occasion when you experience a particularly vexing system problem that can be fixed only by editing a particular value in the Registry. Typically, you'll be instructed to edit the Registry by a tech support person working for the company whose product is causing you problems. (Trust me, it happens.) If this happens to you, you'll need to know how to edit the Registry using the Register Editor utility.

You start Registry Editor by clicking the Start button and selecting Run to display the Run window. Enter regedit in the Open box and then click OK.

The Registry Editor window has two panes, as shown in Figure 21.6. The left pane displays the different parameters or settings, called keys. All keys have numerous subkeys. The right pane displays the values, or configuration information, for each key or subkey.

You display the different levels of subkeys by clicking on the + next to a specific item. You edit a particular value by highlighting the subkey in the left pane and then double-clicking the value in the right pane. This displays the Edit Value (or Edit String) window. Enter a new value in the Value Data box, and then click OK.

To add a new value to a subkey, right-click the subkey and select one of the New, Value options from the pop-up menu. Type a name for the new value, and then double-click the value to display the Edit Value (or Edit String) window. Enter the new value in the Value Data box, and then click OK.

You also can add new subkeys to the Registry. Just right-click the key where you want to add the subkey, and then select New, Key from the pop-up menu. A new subkey (with a temporary name) appears. Type a name for the new subkey, and then press Enter.

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To delete a subkey or value, right-click the item and select Delete. Remember, however, that all changes are final. After a subkey is deleted, it's gone!