The registry is an important component of your Windows operating system. It is comprised of five root keys—HKEY_CLASSES_ROOT, HKEY-CURRENT_USER, HKEY_LOCAL_MACHINE, HKEY_USERS, and HKEY_CURRENT_CONFIG—in which all information related to user preferences, hardware and software configuration and system settings is stored.

To view the registry tree, open the Start menu, select Run, type regedit, and select OK. This will display the Registry Editor window. In this window, you will see a tree-like structure representing the registry. The subtree of each root key comprises several subkeys and their sub-subkeys and each key carries zero or more values.

You can use the Registry Editor tool to perform direct edits to the registry. You can do the edits by navigating to the key that you want to edit and performing the required changes. The tool also enables you to backup the registry by exporting its contents to an external file and helps you manually clean up the registry to keep it free from unwanted debris.

Backup the Registry

It is always recommended that you backup the registry before making any direct changes to it. To back up the registry using the Registry Editor, perform the following steps.

1. Open the File menu and select the Export command.

2. Browse to the location where you want to save the registry backup file.

3. Type the backup file name in the File name box.

4. In the Export Range section select All to back up the entire registry or choose Selected branch and type in the branch to export in the text box provided.

5. Select the Save button to create the backup .reg file.  

Note: You can restore the file by double-clicking the backup file.

Search For and Remove Unwanted Data

Many times, when you uninstall an application, you may want to search the registry and remove any left behind orphan keys. In order to this, in the Registry Editor window, open the Edit menu and select Find. In the Find what box type the name of the program whose entries you want to delete. For instance, to remove entries for a Norton product, you may do a generic search for the keyword ‘Norton’. Next, select the Find Next button to start your search. Keep pressing F3 to continue your search and delete the entries that are not required.

Registry Editing: Tips

Given below are some of the important tips that you may follow while or before making direct edits to the registry using the Registry Editor utility.

Tip #1: Always make a registry backup or export at least the registry branch that you are going to edit.

Tip #2: Create a System Restore snapshot (Windows XP and Windows Vista systems) before starting to perform the edits.

Tip #3: Ensure that the backup you make properly restores the files.

Tip #4: If possible, instead of making direct changes to the registry try to use alternative methods such as changing Control Panel settings or Group Policy settings.

Tip #5: Resort to direct registry edits as the last option, first try to fix the problem through other corrective procedures, such as booting from the Last Known Good Menu, performing System Restore, and scanning the system for virus infections—known to cause several registry errors.

Tip #6: If you are not very comfortable using the Registry Editor to backup the registry, you can use a third-party registry tool to easily create registry backups.

Tip #7: It is recommended that you use a third-party registry cleaner tool to clean your registry and remove registry errors because these tools not only automate and simplify the cleaning process, but also reduce the chances of errors.