How To: Open the Registry Editor
Registry editor is a utility or tool provided by Microsoft with all types of Windows operating systems. This article describes how to open the Windows Registry Editor on different operating systems.
Making any changes in the registry editor without being sure can cause one or more programs or even the Operating System to behave erratically or stop responding.
Pre-requisite
User must have administrator access to Windows Registry.
Steps to do
The Windows registry editor can be opened the following ways.
Opening from the Start menu
(This method applies to Windows XP, Windows Server 2003, Windows 7 and Windows Server 2008)
Click on the Start Menu.
Click on Run.
The Run window opens up.
Type in "regedit " without quotes in the text box.
Click OK.
The Windows Registry Editor will open in a new window.
Opening with Shortcut Key
(This method applies to Windows 8 and Windows Server 2012 as well as all the other versions mentioned above).
Press the ‘Windows’ key and ‘R’ together. Windows key is the key between the Control and Alt key on the left hand side of the keyboard with a 
sign on it.
The Run window opens up.
Type in "regedit " without quotes in the text box.
Click OK.
Click Yes to confirm the Windows UAC prompt.
The Windows Registry Editor will open in a new window.