How to Restore the XP System Registry
- 1). Insert the Windows XP installation CD and restart the computer. When the computer is rebooting, you will see an option to "Boot From CD" (or similar variation). Either highlight the option and press "Enter," or, if prompted, press any key to perform the operation.
- 2). Press "R" on your keyboard in the next screen that comes up. It will say "Welcome to Setup" and "Press 'R' to enter the Recovery Console."
- 3). Select the installation you want to perform the restore procedure on. Most computers only have one installation, unless they are a multi-boot system. If you are unsure, it is unlikely you have more than one.
- 4). Type in the administrator password to enter the installation. If you are unaware of the password and you are the primary user, it is unlikely that you set one up in the first place. Press "Enter" on the blank screen to continue.
- 5). Type the following commands, pressing "Enter" after each one:
md tmp
copy c:\windows\system32\config\system c:\windows\tmp\system.bak
copy c:\windows\system32\config\software c:\windows\tmp\software.bak
copy c:\windows\system32\config\sam c:\windows\tmp\sam.bak
copy c:\windows\system32\config\security c:\windows\tmp\security.bak
copy c:\windows\system32\config\default c:\windows\tmp\default.bak
delete c:\windows\system32\config\system
delete c:\windows\system32\config\software
delete c:\windows\system32\config\sam
delete c:\windows\system32\config\security
delete c:\windows\system32\config\default
copy c:\windows\repair\system c:\windows\system32\config\system
copy c:\windows\repair\software c:\windows\system32\config\software
copy c:\windows\repair\sam c:\windows\system32\config\sam
copy c:\windows\repair\security c:\windows\system32\config\security
copy c:\windows\repair\default c:\windows\system32\config\default - 6). Type "Exit" and press "Enter" on your keyboard. This will exit the Recovery Console and restart your computer.
- 7). Hold the "F8" key down as your computer reboots. This will start the computer in Safe Mode.
- 8). Right-click "Start," then "Explore" to open Windows Explorer.
- 9). Click "Tools," then "Folder Options," then the "View" tab. Click the box "Show hidden Files and Folders." A check mark will appear inside. Click the check mark in the box "Hide Protected Operating System Files (Recommended)" to clear it. This will allow you to work with and manipulate files you would not normally have access to. Click "OK" and confirm your choice.
- 10
Open the folder c:\system volume information. It will be dimmed and appear inaccessible. This folder contains system restore points. You can identify them by their names. They begin with "_restore," and have a large combination of letters and numbers surrounded by "{ }." - 11
Open one of the folders from a previous date when you knew the system worked. (The most recent folder will be from the day you are performing the procedure; you don't want that one.) Open the subfolder that ends with "Snapshot." - 12
Copy the following files from the snapshot folder:
_REGISTRY_USER_.DEFAULT
_REGISTRY_MACHINE_SECURITY
_REGISTRY_MACHINE_SOFTWARE
_REGISTRY_MACHINE_SYSTEM
_REGISTRY_MACHINE_SAM
Do this by highlighting then right-clicking them. Select "Copy" from the menu that pops up. - 13
Paste them into the folder c:\windows\TMP. Right-click any unoccupied space in the folder and select "Paste." - 14
Rename the copied files as follows:
"_REGISTRY_USER_.DEFAULT" becomes "Default"
"_REGISTRY_MACHINE_SECURITY" becomes "Security"
"_REGISTRY_MACHINE_SOFTWARE" becomes "Software"
"_REGISTRY_MACHINE_SYSTEM" becomes "System"
"_REGISTRY_MACHINE_SAM" becomes "Sam"
Accomplish this by right-clicking each file and selecting "Rename." - 15
Repeat steps 1 and 2 to re-enter the Recovery Console. - 16
Type the following commands at the prompt in the Recover Console, pressing enter between each one:
del c:\windows\system32\config\sam
del c:\windows\system32\config\security
del c:\windows\system32\config\software
del c:\windows\system32\config\default
del c:\windows\system32\config\system
copy c:\windows\tmp\software c:\windows\system32\config\software
copy c:\windows\tmp\system c:\windows\system32\config\system
copy c:\windows\tmp\sam c:\windows\system32\config\sam
copy c:\windows\tmp\security c:\windows\system32\config\security
copy c:\windows\tmp\default c:\windows\system32\config\default - 17
Type "Exit" and press "Enter" on your keyboard to reboot once again. This time let Windows boot normally. - 18
Click "Start," then "All Programs," then "Accessories," then "Tools," then "System Restore." Choose the option to "Restore to a Previous Restore Point." Follow the onscreen instructions to restore the rest of your settings. This is done to make sure the rest of the computer's functionality is restored along with the registry. It will not affect files or saved emails, so it is a good idea to utilize the program, even if you are confident in the registry restoration.
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