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Registry Tutorial - Part 1


The Windows Registry a set of files that describe how your operating system (Windows itself), hardware such as printers, scanners, etc., software programs and other parts of your system function. You can tweak (edit) the Registry to improve or alter the way your computer performs.

Editing the Registry is not for the faint of heart, however. Think of editing the Registry as you would performing neurosurgery: Once you start, you're committed. You either do it well or it's best not to attempt it in the first place.

Due to the length of this tutorial, it is divided into three parts. If Part 1 doesn't put you to sleep, surely Parts 2 or 3 will get the job done. You are currently reading Part 1, which includes the following sections:

What is the Windows Registry?
Backup Your Registry Before Editing!
Registry Backup and Restoration
Windows 95
Windows 98

What is the Windows Registry?

The Windows Registry a set of files that describe how your operating system (Windows itself), hardware such as printers, scanners, etc., software programs and other parts of your system function.

Every time you install hardware or software, it's recorded in the Registry along with the settings that permit the new program or device to operate with the rest of your system. Whenever you remove something or change your settings, those changes are also monitored in the Registry.

Backup Your Registry Before Editing

If you make a mistake when editing the Registry, you may discover that your computer no longer works or has been adversely affected in some other way. So don't change anything unless you know what you're doing, or you are following very specific instructions.

The Golden Rule of Registry Editing: Backup, backup, backup. Make sure you have your Registry backed up, so you can always return to an earlier version if you mess things up badly. Let's take a look at backing up and restoring your Registry before moving into the realm of Registry editing.

Another word of caution: As you review the following information about backing up and restoring your Registry files, if this sounds too advanced or you don't understand some of the terminology, do not attempt any Registry edits. Think of it as you would neurosurgery: You can't dabble in it. You either do it and do it well, or it's best not attempted at all.

Registry Backup and Restoration

All versions of Windows keep previous versions of the Registry on your hard drive, although not as up to date as you might need. In Windows 95, Registry information is kept in two files, System.dat and User.dat, in the Windows directory. Whenever Windows is started, it stores a backup of these Registry files as System.da0 and User.da0. (Those are zeros on the end of the file names, not the letter "O.")

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Windows 95

If you mess up your Windows 95 Registry so that you can't restart Windows, you can work in DOS to replace the two .dat files with the .da0 copies. If you're not familiar with or comfortable working in DOS, my best recommendation is do not attempt to edit your Registry unless you have somebody who is familiar with DOS standing by to help you out if you get into trouble. If the following instructions are meaningless to you or you're not familiar with the concept of file attributes, my best advice is do NOT attempt to edit your Registry:

To replace the .dat files with the .da0 files, first remove the three attributes (Hidden, Read-only and System) from the .dat and .da0 files with DOS commands like attrib -r -h -s c:\windows\system.dat for each of the files. Then rename the two .dat files to end in .bak, rename the .da0 files to end in .dat and restart the computer. Then give the Hidden, Read-only and System attributes back to the new .dat files with attrib +r +h +s c:\windows\system.dat and so on.

Windows 98

Windows 98 makes it a bit easier. Whenever you start your computer, Windows bundles the two .dat files together with two other system files, System.ini and Win.ini, and compresses them into a .cab file in the Windows\Sysbckup folder. Up to five of the most recent versions of this file are kept there, numbered to

You can use Win98's System Info utility to make .cab backups. You can access this utility by clicking Start > Programs > Accessories > System Tools, then click System Information. Under the Tools menu, click Registry Checker. When asked if you want to make a new backup, answer "Yes." This will delete the oldest of the five .cab files and create a new one.

If your Registry edits result in your Windows 98 system no longer functioning, after you regain consciousness, you can restore it to a previous .cab and be back in business by following these steps:

First, restart your computer in DOS. If you can't do this by selecting "Restart in DOS" during the shutdown procedure, turn off the computer completely.

Then, turn it back on and press the F8 function key repeatedly during the bootup process until you are presented with the Microsoft Startup menu.

Select "Command prompt only" and you will be face to face with a DOS prompt. In the DOS Windows directory (C:\WINDOWS\>) enter the command "scanreg" (without the quotes) at the prompt. When asked, "Agree" to check your Registry. Next, select the option to view your backups. A list of the .cab files will appear, letting you choose which one to restore.

Even easier, you can get scanreg to restore your Registry to its last known functional state by entering, at the DOS prompt, the command "scanreg/restore" (without the quotes).

Next Article: Registry Part 2 which contains the following sections:

Windows Me
Windows XP
All Versions of Windows
Accessing the Registry
Editing the Registry
Deleting and Adding Values

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