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The Registry lies at the heart of Windows, controlling how your OS interacts with your hardware and applications. So what do you do when it starts to play up?

The Registry

The Windows Registry is a database of settings for all the hardware, software and different user preferences on your PC. Whenever you add hardware, uninstall a program or change the resolution of your display, it’s the Registry that holds the data about this change.

It works away in the background and is not designed to be accessed or edited by the casual Windows user. This is because making an incorrect entry in the Registry can cause major problems, including your PC no longer starting. For this reason you shouldn’t start tweak Registry settings unless you’re confident about the changes you’re making and have a backup plan in place. That said, there are times when being able to access and edit the Registry can be incredibly handy, healing a sick PC in minutes. We’re going to show you how to access and back up your Registry, plus solve common problems with a simple setting change.

Registry Q & A

How can I access the Registry to make changes to it?

The Registry data is contained within a handful of files, depending on the Operating System you use. For example, in Windows 98 there are two hidden files called User.dat and System.dat in your Windows directory. However, you can’t open and edit these files directly and Windows comes with a tool called the Registry Editor for making changes. You can access this tool in all versions of Windows by pressing Start, Run, typing regedit and pressing OK.

How do I go about backing up the Registry?

Understanding whether you have a good backup and how to restore it if things go wrong is one of the most important questions you should address before attempting to make any changes. The process varies according to your version of Windows.

For Windows 98 press Start, Run, type scanregw and click OK. When you receive a prompt to back up the Registry click Yes and then press OK when you’re informed that the process is complete.

My Windows 98 Registry is working OK, but the associated files have grown massively and there are loads of redundant entries in there.

The longer you run a PC without a clean reinstall, the more your Registry files grow. This is just a fact of Windows and over time it can cause your PC to slowdown. While Windows is good at adding and tracking changes in your Registry, tasks such as uninstalling software do not always cause the Registry entries to be removed. There’s a utility for Windows 98 called RegClean that can help you get rid of all these erroneous entries and speed up your PC in the process. You can download it from

How do I create new Keys, String values, or edit value data in the Registry Editor tool?

Just browse to the key you’re interested in. If you want to create a new subkey for this key, or a new value within this key, then right-click it and select New. You can then choose to create a new key or new value type as required. To edit value data, browse to the value and simply double-click it. If the data can be edited then a box will appear that you can simply type the new data into.

Sometimes when I click on my mouse, it acts as if I have clicked it twice, rather than once.

There is a setting in the Registry that you can switch on to detect accidental double mouse clicks. Browse to HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced, create a new String value called UseDoubleClickTimer and set the value data to 1.

My Windows text is difficult to read, with jagged edges on the letters. I have checked that the fonts are installed correctly. What can I do?

A Registry setting can smooth the fonts displayed on your PC by using anti-aliasing. It’s set on by default, so it may be that this has value has been modified, or deleted. Browse to HKEY_CURRENT_USER\Control Panel\Desktop and see if the String FontSmoothing is present. If it’s there set the value to 2. If it isn’t, recreate it.

I love the thumbnail view in Explorer, but is there a way that I can make the pictures easier to see?

Browse to HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer. Create or modify two DWORDs called ThumbnailSize and ThumbnailQuality. For ThumbnailSize set the value in pixels, with the default being 96. For ThumbnailQuality set the value as a number that represents the percentage quality between 50 and 100.

I have programs still listed in the Add/Remove programs dialog even though they have already been uninstalled. How do I get rid of them?

The Registry can help you get rid of these redundant entries. Browse to the following key: HKEY_ LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall.

You will find a collection of subkeys beneath this key, each one representing an entry in the Add/Remove programs dialog. Click any subkey to see the program that it is associated with, which can be viewed in the DisplayName value. Delete the subkey to remove the entry.

A simple Registry tweak

To understand the principles of altering the Registry, follow this simple tweak for changing the Number Lock status.

Press Start/Run and type regedit to launch the Registry Editor. Use the Explorer-style browse tree in the left-hand pane to find HKEY_USERS\.DEFAULT\Control Panel\Keyboard.

Look in the right-hand pane for the value InitialKeyboardIndicators and double-click it. In the Edit String dialog box change the Value data to either 0 for Off or 2 for On. Press OK and close the Registry Editor.

The change made will apply to all users, but if you want to make the change just for yourself and not for other users on the PC then you can do this by making the same changes to the following key: HKEY_CURRENT_USER\Control Panel\Keyboard.

Registry Help

Where can you go to get advice on understanding and modifying the Registry?

If you find yourself in need of help and we’re not at hand, there’s one online source that stands head and shoulders above the rest.

Formerly known as, the Windows Registry Guide can be found at You’ll find detailed tutorials explaining what the Registry is and how it works. There are links to a host of utilities that can help you make the most of your Registry and keep it fine tuned. Most important of all, you’ll find just about every tweak you’ll ever need, divided into helpful sections. These range from fixing problems with hardware and software, through to tips and tricks that will optimise your system.

The Registry is one of the most powerful components of your Operating System and the Windows Registry Guide can help you unlock its full potential. You can even access the contents of the guide when you’re not online by downloading and installing a small application from
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Artikel-id: 835823 – senaste granskning 8 juli 2008 – revision: 1