Microsoft KB Archive/131352

Using Registry Editor in Real Mode

Q131352

The information in this article applies to:

Microsoft Windows 95

IMPORTANT: This article contains information about editing the registry. Before you edit the registry, you should first make a backup copy of the registry files (System.dat and User.dat). Both are hidden files in the Windows folder.

SUMMARY

The registry is a system-wide database used for storing Windows 95 soft- ware and hardware configuration settings. The registry consists of the System.dat and User.dat files, which are located in the Windows folder. These files are backed up as System.da0 and User.da0 after every successful boot of Windows 95.

Windows 95 includes a Registry Editor program (Regedit.exe) that runs in both the real-mode MS-DOS environment and in the protected-mode Windows environment. When you need to modify the registry without starting Windows 95, use Registry Editor in real mode. Note that the switches listed in this article only work in real-mode.

MORE INFORMATION

WARNING: Using Registry Editor incorrectly can cause serious problems that may require you to reinstall Windows 95. Microsoft cannot guarantee that problems resulting from the incorrect use of Registry Editor can be solved. Use Registry Editor at your own risk.

NOTE: For information about how to edit the registry, view the Changing Keys And Values online Help topic in Registry Editor (Regedit.exe). Note that you should make a backup copy of the registry files (System.dat and User.dat) before you edit the registry.

To export, modify, and then import registry data using Registry Editor in real mode, follow these steps:

Restart your computer. When you see the "Starting Windows 95" message, press the F8 key and then choose Safe Mode Command Prompt Only from the Startup menu.
Change to the folder in which Windows 95 is installed by typing the following command at the command prompt, and then press ENTER

cd\<windows>

where <windows> is the folder in which Windows 95 is installed.
Make a backup of the registry. To do so, type the following commands at the command prompt, pressing ENTER after each command:

attrib -s -h -r *.dat

copy user.dat user.sav

copy system.dat system.sav

For more information about backing up the registry, see the following article in the Microsoft Knowledge Base:

Q132332 How to Back Up the Registry
To export the registry to a text file, type the following command at the command prompt, and then press ENTER:

regedit /e registry.txt

This command exports both the System.dat and User.dat files. By default, the Registry.txt file is saved in the folder from which you run Registry Editor.

To export a specific registry key to a text file, type the following command at the command prompt, and then press ENTER

regedit /e regkey.txt <registry key>

where <registry key> is the key you want to export. For example, type the following command:

regedit /e regkey.txt "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\ Microsoft Office\95\Microsoft Network"

NOTE: This line is wrapped for readability. This should be typed as one line.
Using a text editor (such as Edit.com), modify the Registry.txt file you created in step 4, and then save and close the file.
To merge or import the text file back into the registry, type the following command at the command prompt, and then press ENTER:

regedit registry.txt [without /c]

If you want to create a new registry from the exported text file and replace the existing registry files, type the following command at the command prompt, and then press ENTER:

regedit /c registry.txt

Creating a new registry file from exported text can be used as a troubleshooting technique to repair a damaged registry. For more information about troubleshooting registry problems in real mode, see the "Using Real-Mode Registry Editor" section of the following article in the Microsoft Knowledge Base:

Q131431 How to Troubleshoot Registry Errors

The changes take effect the next time you start Windows 95. If the changes you make cause problems in Windows 95 or you want to revert to the registry before you made the changes, restart your computer, press the F8 key when you see the "Starting Windows 95" message, and then choose Safe Mode Command Prompt Only from the Startup menu. At the command prompt, type the following commands, pressing ENTER after each command:

cd\<windows>

attrib -s -h -r *.dat
ren user.dat user.bad
ren system.dat system.bad
copy user.sav user.dat

copy system.sav system.dat

NOTE: If user profiles are enabled in Windows 95, the above procedure only changes the User.dat file in the Windows folder. It does not make any changes to the User.dat file in the <windows>\profiles\<username> folder, (where <username> is the name you use to log on to Windows 95.

If you want to modify only the System.dat or User.dat file, or if there is a problem working with both the User.dat and System.dat file in one registry file, there are switches you can use that enable you to work with specific files. For information about problems with importing a registry with large keys, see the following article in the Microsoft Knowledge Base:

Q132064 REGEDIT May Not Be Able to Import Registry with Large Keys

The following procedure gives the commands for changing step 4 above, which exports the entire registry, and step 6 above, which imports the text file (in this instance, the User.dat file):

Step 4:

To export the User.dat file to a text file located in the root folder, type the following command at a command prompt, and then press ENTER:

regedit /l:c:\windows\user.dat /e c:\user.txt

Step 6:

To merge or import the User.txt file back into the registry, type the following command:

regedit /l:c:\windows\user.dat c:\user.txt [without /c]

If you want to create a new User.dat file from the exported text file, thereby replacing the existing User.dat file, type the following command at a command prompt, and then press ENTER:

regedit /c registry.txt

Syntax

The syntax and command-line switches for using Regedit to import to, create, or export from the registry in real mode are as follows:

To merge or import a text file into the registry, use the following command:

regedit [/L:system] [/R:user] filename1

To create and replace an existing registry from a text file, use the /c switch as follows:

regedit [/L:system] [/R:user] /C filename2

To export text from the registry, use the /e switch as follows:

regedit [/L:system] [/R:user] /E filename3 [regpath]

To see this list, type regedit /? at the command prompt.

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Issue type :
Technology : kbWin95search kbWin95