It's the beginner's survival guide to using the Registry in Windows - discover how to back it up, access it and tweak it for troubleshooting and performance-boosting purposes. Part one of two
he Registry is a vital component in Windows, a central database that contains most of the key settings and preferences for Windows itself, plus your programs and hardware. The Registry can be edited using the Registry Editor, and you'll notice we often make reference to it elsewhere on the site, whether it's to change a system setting, improve performance or fix a problem in Q&A. However, a lot of people are reluctant to get their hands dirty in this way, aware that it's theoretically possible - if unlikely - to mess up your PC by doing so.
In this two-part feature we'll introduce you to the Registry. We'll show you what it does and reveal how it works. Discover how to safely make changes to your system, either using Registry Editor or a selection of more hands-off methods. We'll also show you how to back it up so your changes can't do any lasting damage, even in the worst-case scenario.
How it works
The Registry is made up of a group of files called "hives", which are stored in two separate folders on your hard drive: the Windows\System32\Config folder for system-wide settings, and your personal Documents and Settings folder for settings associated specifically with your user account.
Each hive consists of a different set of preferences and configuration data - for example, the system-wide software settings are stored in a file called SOFTWARE. This information is organised into folders and sub-folders known as "keys" and "subkeys". Each key contains one or more "values" with their associated "value data", which are the actual configuration settings for your PC.
There are five different types of value depending on the data they contain, but two of the most common are DWORD values, which are numbers that can be binary or hexadecimal, and Expandable String Values, which contain text like drive labels, context-menu options or the path to a particular folder or file on your hard drive.
Whenever Windows, a program or hardware device needs certain settings or information, it consults the Registry for the specific values it needs, enabling it to function correctly. These keys, subkeys and values are usually added when the software or hardware is first installed, and organised in such a way as to be accessible (many software and Windows settings are found inside the HKEY_CURRENT_USER\Software key, for example).
Step-by-step:
Back up your Registry
1. BACK UP FIRST
The simplest thing to do before making your changes is take a Restore point - click Start > All Programs > Accessories > System Tools > System Restore.
2. EXPORT FROM REGISTRY EDITOR
You can also back up from within Registry Editor. Select the key containing the subkeys or values you're about to edit and choose File > Export.
3. BACK UP KEY
Make sure the selected branch is picked, choose a back-up location (My Documents is selected by default), give your backup file a suitable name and click Save.
4. FAIL-SAFE BACKUP
To provide additional protection against Registry corruption in Windows, download and install ERUNT from here - this backs up the Registry each time Windows starts.
5. SET PREFERENCES
During installation, allow the program to run automatically. Untick Show Documentation and click Finish to allow ERUNT to launch for the first time.
6. SET BACK-UP LOCATION
By default, ERUNT backs up to the Windows folder - leave this selected as it enables you to recover the Registry using the Recovery Console (XP) if necessary. For more on recovering from Registry corruption, click here.
Viewing the Registry
Windows features a tool called Registry Editor, which enables you to take a peek at these Registry keys. You can also add your own subkeys and values, plus edit or delete existing ones. For now though, let's just take a look at what's there. Click Start > Run, type regedit and press [Enter].
You'll see a two-paned window - in the left are the keys and subkeys, while the right-hand window displays the values currently associated with the currently selected key. In terms of Windows and application settings, the best key to start looking inside is the HKEY_CURRENT_USER key. Double-click this, and you'll see its subkeys appear. Double-click one of these, and its subkeys will appear, and so on and so forth.
If you just select a key by clicking it, you'll see its associated values appear in the right-hand window. It's these values that determine the various settings in Windows, your programs and so on. For example, browse to the following Registry key: HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer. With Explorer selected, take a look in the right-hand pane at the Logon User Name entry, which you'll recognise as being that of your user account. If you were to change this in the User Accounts Control Panel, this value gets amended.
Q&A
I find it annoying having to move between different parts of the Registry. Is there a quicker way to get to the subkeys I need?
Although Registry Editor remembers the last key you visited, it can be time-consuming and frankly quite annoying finding your way back to a key the second time around. If you find yourself needing to access a key on a regular basis - HKEY_CURRENT_USER\ Software\Microsoft\ Windows\CurrentVersion comes to mind - then select the key and choose Favorites > Add to Favorites. Give it a name and click OK, and it'll be accessible from the Favorites menu in future.
Annotation: Exploring Registry Editor
A. NAVIGATION TREE
The left-hand window contains your Registry keys, which are arranged in a hierarchical fashion.
B. EXPAND KEYS
To expand a key, either click the + symbol next to it or double-click it. All of its subkeys will appear as a folder-like structure similar to Windows Explorer.
C. VALUES
The values associated with the currently selected key or subkey in the left-hand pane are displayed here, along with their value data.
D. CREATE/MODIFY KEYS
Right-click a subkey to get a number of options. You can delete or rename the key, but choose Export first to back it up.
E. NEW VALUES
Select New to create a new subkey inside the currently selected key, or to pick a particular value to associate with the currently selected key.
F. EDIT VALUE DATA
Double-click a value in the right-hand pane to change its value data. The Edit box changes depending on the type of value you're modifying.
