How to Remove a PC ID From the Registryby Jim Campbell
Your computer ID is stored in the Windows registry. The ID is given to the computer when you install the Windows operating system. If you want to remove this computer name, you delete the value from the Windows registry. The ID given to the computer is called the "computer name," and this registry key is the one you edit when you want to remove the ID from the system. You can also use this key to change the computer's ID.
Click the Windows "Start" button. Type "regedit" into the text box in the pop-up menu. Press "Enter" to open your Windows registry editor.
Navigate to "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\ComputerName\" in the registry. This contains the keys to identify your computer.
Double-click "ActiveComputerName." In the "Value" text box, clear the text to remove the name. You can also enter a new computer ID for the machine. Click "OK" to save the changes.
Reboot the computer. Changes to the registry do not take effect until you reboot.