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