Registry Editor

Before you start

Objectives: learn what is Registry and where to find and how to use Registry Editor.

Prerequisites: no prerequisites

Key terms: registry, editor, entry, configuration, value, regedit, setting, software


The Registry is a database that holds hardware, software and user configuration settings. For example, when we’re working in the Control Panel and we make a change to a setting, that setting is saved in the Registry. When Windows starts and loads our individual preferences and configuration information, it will load that information from the Registry.


Normally we will use Control Panel and other applets to make system configuration changes. All those applets provide us an interface for identifying and changing the settings within the Registry. However there are cases where we might need to view or even edit the Registry directly. While this is usually not recommended, we would edit the Registry directly when there is a setting that does not have a corresponding applet for us to change. The Registry editor application is regedit.exe, and to run it we can simply enter ‘regedit‘ in Search or Run, and hit Enter.


Image 210.1 – Registry Editor

If you’re working in Windows 2000, regedit will open a limited version of the Registry Editor which does not include all of the features that we might need. In Windows 2000 we should use the regedt32.exe program instead of usingregedit. If we are using Windows XP or later, we can use either regedit orregedt32, both will open the same utility.

The Registry is a database of settings that are being applied to the computer. The Registry is divided into hives. Each hive represents a different portion of configuration information. For example, theHKEY_USERS hive contains information about the users that have been configured on our computer. The HKEY_CURRENT_CONFIG hive shows software and system configuration information that is currently being used by this running instance of the operating system.

Example Configuration

To get a grasp on how to work with Registry Editor we will take an example of configuring auto login feature trough Registry Editor. Let’s browse to theHKEY_LOCAL_MACHINE > SOFTWARE > Microsoft > Windows NT > CurrentVersion > Winlogon. Make sure that the Winlogon is selected.


Image 210.2 – Winlogon

On the right hand side we can see individual settings that are stored in the registry. Those are called keys. A key has a name and a value or the dataassociated with the key. Within the Registry Editor we can double click on the key and change the value associated with that key. Let’s double-click theDefaultUserName entry, type our user name, and then click OK. In our case we have an Admin user which we want to auto login when we power on our computer.

Default User Name

Image 210.3 – Default User Name

When changing values we have to be careful. If we make changes that are wrong, installed software or even operating system could cease to function properly. Next, we have to double-click DefaultPassword entry. If there is no DefaultPassword entry, we have to add it. To add new entry, in Registry Editor menu click Edit, click New, and then click String Value. TypeDefaultPassword as the value name, and then press Enter. So, we will double-click newly created DefaultPassword entry, type in our password in the Value data box and click OK.

Setting Password

Image 210.4 – Default Password

Next, double-click the AutoAdminLogon entry, type 1 in the Value data box, and then click OK.

Auto Admin Logon

Image 210.5 – Auto Admin Logon

If there is no AutoAdminLogon entry we can manually create this entry too. That is it. When our computer restarts, the Admin user will be loged on automatically.

Typically we will not manually modify the Registry unless it is the only way to solve a particular problem. For our example, we could turn on automatic logon without editing the Registry, using ‘control userpasswords2‘ tool.


The Registry is a database of settings that are applied to the computer. The Registry is divided into hives. Each hive represents a different portion of configuration information. The Registry editor application is regedit.exe.