Please note that the following article is provided by TechTV.

I show a lot of Registry hacks. But if you don't feel familiar with the Registry and its components, you won't benefit from many of my tweaks. I won't stand for that!!! On this show, I want to make you comfortable enough to manipulate the Registry four ways from Sunday.

O'Reilly's put together an excellent page at its website that explains the details of how the Registry works. That's a good place to brush up before you watch this show. I also highly recommend the accompanying book, "Windows XP Hacks."

If you don't have time to dive into that article, let me fill you in on the basics.

Registry divided into hives

The Registry is divided into five areas called hives. The hives themselves are stored in the C:\Windows\system32\config and C:\Documents and Settings\ {username} files.

The five Registry hives


This mostly contains information about file types and file name extensions. It tells XP how to handle the different file types and which user interface options to use.


Here's where the system keeps information about every user on the system.


This hive contains system setup info for the machine's current user. This includes things such as desktop preferences, printers, and security settings.


This hive stores information about the computer itself and the hardware attached to it, such as keyboards, storage, and such.


Here's the hive that keeps current hardware configurations during the active session.

Using keys and values

Underneath each hive are keys that can contain subkeys, and those subkeys can have subkeys, and so on and so on.

Keys and subkeys contain values. That's how the Registry controls things. Change the values and you change the thing the key controls.

O'Reilly uses this key as an example.

HKEY_CURRENT_USER\Control Panel\Mouse\DoubleClickSpeed

It controls the time between clicks that determines whether something is a double-click or not. You have to edit the key's value to change the time.

Editing a Registry key's value

Here are the five primary data types in a Registry.

* REG_SZ (string value) -- numbers and text
* REG_MULTI_SZ (string array value) -- numbers and text you can edit but not create
* REG_EXPAND_SZ (expanded string value) -- usually points to the location of files
* REG_BINARY (binary values) -- binary data
* REG_DWORD (DWORD values) -- a hexadecimal data type

To edit the Registry, use the Registry Editor

OK, time again to warn you. Don't play with the Registry unless you know what you're doing. You can really mess stuff up. To run the Registry Editor, go to the Run box in Windows and type "regedit" (without quotes), then press Enter.

The Registry Editor works like Windows Explorer. Changes you make take effect either right away or after a reboot. Keep in mind though that every change you make is permanent. There's no undo button. Did we mention being careful? Be careful!

A good trick when you're searching for a particular key is to use the find command. Press Ctrl + F to launch it.

Again, for all the details, visit the O'Reilly article we mentioned at the top of this piece.

Lastly, if you don't understand the title of this article, please rent this.

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