I know there are hundreds of freeware and shareware programs that customize the registry with the click of a mouse. This article is for those who’d like to tinker with the registry and discover the mystery inside. So, power users get prepared to delve into the mucky waters of the Windows registry.

Before starting off, make sure that you back up your registry. This can be done in many ways. You can copy the files—user.dat, system.dat—to a floppy diskette. Or, start up the Registry Editor by executing regedit. Select the Export Registry File menu by clicking on the “Registry” tab, and export your registry to a *.reg file, which when double-clicked will restore your registry to its previous state. You could also use registry backup software, such as Microsoft Registry Backup, RegBackup, etc, to back up your registry.

Here are some of the things you can do by tweaking your registry.

Change username and organization information
Locate the registry key
HKEY_LOCAL_MACHINE\SOFTWARE\ Microsoft\Windows\CurrentVersion
Look for the entries RegisteredOrgani sation and RegisteredOwner in the right-window pane. By double-clicking these, you can edit both the properties, and change user information.

Remove the arrow from shortcuts
Open the registry keys
HKEY_CLASSES_ROOT\lnkfile
HKEY_CLASSES_ROOT\piffile
HKEY_LOCAL_MACHINE\Software\ Classes\lnkfile
HKEY_LOCAL_MACHINE\Software\ Classes\piffile
Under each of these, delete the entry IsShortcut.

Remove unwanted icons from your desktop
Open the registry key
HKEY_LOCAL_MACHINE\Software\ Microsoft\Windows\CurrentVersion\ Explorer\Desktop\Namespace
Click on any of the various binary ID numbers that are sub-keys of this key.

The corresponding item for the selected binary ID will then be displayed. 

For example, selecting {450d8fba-ad25-11d0-98a8-0800361b1103} will display “My Documents”.
Delete the binary ID sub-key for all the icons that you want to remove from your desktop.

Removing the Add/Remove Programs entries
If you’ve uninstalled some software, but it still has its entry in the Add/Remove Programs menu, you can remove it by deleting the appropriate sub-key under the entry HKEY_LOCAL_MACHINE\Software\ Microsoft\Windows\CurrentVersion\Uninstall

Preventing modem inactivity timeouts
Open the registry key
HKEY_LOCAL_MACHINE\System\ CurrentControlSet\Services\Class\Modem\0000\Settings
Change the number in the InactivityTimeout value to the time you want (in minutes).

Adding “DOS Prompt Here” to the Right-click menu
Open the registry key
HKEY_CLASSES_ROOT\Directory\shell
and create a new sub-key titled CommandPrompt. Change the value of Default from “value not set” to “&Dos Prompt Here”. Create another sub-key under the CommandPrompt key, and name it Command. Change the value of its Default from “value not set” to
command.com /k cd “%1”.

Prevent “Shortcut to...” from being prefixed to a shortcut you create
Open the registry key
HKEY_CURRENT_USER\Software\ Microsoft\Windows\CurrentVersion\Explorer
Change the value of the link property to “00 00 00 00”.
To restore it, change the value to 
“10 00 00 00”.