| The Windows registry is a database which stores | | | | configuration, as they can just work with the 'current |
| settings and options for the operating system for | | | | user' key, whereas in the past they tended to just |
| Microsoft Windows 32-bit versions, 64-bit versions | | | | keep system-wide per-program settings. There are |
| and Windows Mobile. | | | | always some system wide settings that are common |
| It contains information and settings for all the | | | | for all users though. |
| hardware, software, users, and preferences of the | | | | * Group Policy allows administrators on a |
| PC. Whenever a user makes changes to "Control | | | | Windows-based computer network to centrally |
| Panel" settings, or file associations, system policies, or | | | | manage program and policy settings. This is not used |
| installed software, the changes are reflected and | | | | in a home environment, only in corporations with a |
| stored in the registry. | | | | dedicated logon server. |
| The registry is actually a big file where a lot of | | | | * Because the registry is accessed through a special |
| setting can be stored. | | | | API it is available to scripts and remote management |
| This file has been around quite a while and has had | | | | using WMI. Each script does not have to be |
| different names. | | | | customised for every application's unique |
| The first windows version that used the windows | | | | configuration file layouts and restrictions. |
| registry to store settings was windows 3.11 and the | | | | * The registry can be accessed as one item over a |
| registry in that version of windows was called | | | | network connection for remote management |
| Reg.dat. | | | | support, including from scripts, using the standard |
| In Windows 95 & 98 the registry files are named | | | | API. |
| User.dat and System.dat and are stored in the | | | | * It can be backed up more easily, in that it is just a |
| \Windows\ directory. | | | | small number of files in specific locations. |
| Windows ME called the registry files, Classes.dat, | | | | Bad things with the Registry |
| User.dat, and System.dat and stored them in the | | | | Not all that shines is gold. The Registry introduces |
| \Windows\ directory. | | | | some problems as well: |
| Finally the newest versions of windows like, Windows | | | | * It is a single point of failure - damage to the |
| NT, 2000, 2003, & XP stores the registry files like | | | | Registry can render a Windows system unbootable, |
| this, | | | | in extreme cases to a point that can not be fixed, |
| The Registry files are stored in | | | | and requires a full reinstall of Windows. This is why it |
| %SystemRoot%\System32\Config\: | | | | is so important to use registry scan and repair utilities, |
| - Sam | | | | while the registry still can be repaired. |
| - Security | | | | * Any program which wants to manipulate the |
| - Software | | | | registry must use special Windows API functions |
| - System | | | | whereas a configuration file can be manipulated using |
| - Default | | | | normal text file-processing techniques. |
| - Userdiff | | | | * Configuration files can contain comments to help |
| - NTUSER.dat | | | | the user by explaining what values are for and how |
| - The NTUSER.dat file is stored in the profile folder. | | | | they can be changed, the registry cannot. And the |
| The Windows Registry was introduced to tidy up the | | | | registry use something called guids in a large scale. |
| old way of storing text entries in INI files. These | | | | Long strange unique numbers that is completely |
| entries had previously been used to store | | | | meaningless to humans. Making handling much harder. |
| configuration settings for Windows programs. | | | | * It is more difficult to backup - it cannot be done |
| The ini files where stored in a lot of different | | | | 'live' because it is always in use, and thus requires |
| directories and many programs used their own ini file | | | | special software such as ntbackup. |
| for some or all of their settings. This way of using ini | | | | * Restoring parts of the registry is hard because you |
| files all over the system, made them difficult to keep | | | | cannot easily extract data from backed up registry |
| track of and handle in an easy and logical way. | | | | files |
| What's Good with the Registry | | | | * Any application that doesn't uninstall properly, or |
| Changing from having one or more INI Files per | | | | doesn't have an uninstaller, can leave entries in the |
| program to one centralised registry has some | | | | registry, which can lead over time to increased file |
| obvious and some not so obvious benefits: | | | | size and decreased performance. And once again, |
| * The registry keeps machine configuration separate | | | | here's the major reason why you must use a registry |
| from user configuration. When a user logs into a | | | | scan/clean and repair software. |
| Windows NT/XP/2003 computer, their registry | | | | The registry will be redone once more with the |
| settings are merged with the system wide settings. | | | | release of the new Vista Operating System from |
| This allows programs to more easily keep per-user | | | | Microsoft. |