The registry is nothing more then a central lace to store all settings on the computer. You should not need to male manual change to the registry because programs and application typically make all the necessary change automatically. The registry .INI “interpretation” stored each program settings in to text file. 1. Regedit 2. Regedit32/64 3. Reg

1. SEMINAR
REGISTRY
Mr.Alok Sharma
M.Tech Class Coordinator
Dr.Rajesh Bhagat
HOD (CSE/IT Department)
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2. What is Registry ?
The registry is nothing more then a central lace to store all settings on the computer.
You should not need to male manual change to the registry because programs and
application typically make all the necessary change automatically. The registry .INI
“interpretation” stored each program settings in to text file.
Windows comes with one to three different registry editing tools for you to use :1. Regedit
2. Regedit32/64
3. Reg
Why does Windows need a Registry :- All operating systems need a way to store
information about the system. There is more than one way to do
this and Apple
and Linux use a different method. Windows kept information in a large number of
separate INI files scattered throughout the system. Then, beginning with Windows 95,
Microsoft decided to centralize the information.
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3. Registry Key
Structure
The Registry has a hierarchal structure, like the directory structure on your
hard disk, the operating system the registry in regedit.exe you presented
with five to seven.
1.
2.
3.
4.
5.
6.
7.
HKEY_CLASSES_ROOT
HKEY_CURRENT_USER
HKEY_USER
HKEY LOCAL MACHINE
HKEY_CUNRRENT CONFIG
HKEY_DYN_DATA
HKRY_PERFORMANCE_DATA
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4. HKEY_CLASSES_ROO
T
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5. HKEY_CURRENT_USE
R
Contains the root of the configuration information for the
user who is currently logged on. The user's folders, screen
colors, and Control Panel settings are stored here. This
information is referred to as a user's profile.
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6. App Events:- This sub key contains paths to sound files that are loaded for specific
system events (for example, when an error message occurs).
Consol:- The Console key stores data for the console subsystem, which hosts all
character-mode applications, such as Command Processor. In addition,
the
Console key can contain sub keys for custom command windows.
Control Panel :- The Control Panel key and its sub keys contain entries that
specify the accessibility, regional, and desktop appearance settings “Keyboard,
Mouse,Color,ScreenSaver and plug-unplug etc.”.
Software :- The Software key stores program variables that are specific to the
current user. The system stores some of its variables in this key. In addition, the
Software key contains sub keys representing the vendors, including Microsoft,
who produced the software running on the system.
Network:- The Network key stores information about mapped network drives
“Connect and Reconnect at logon”.
Environment:- The Environment key stores the values of environment variables
that users can set. Each entry in this key associates an environment
variable with the path that is substituted for the variable. The user's profile
defines the default values for these entries.
%USERPROFILE%Temp
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7. HKEY_LOCAL_MACHINE
The Contains information about the Hardware and Software settings that
are used for all users of this computer.
Hardware:- Information passed to Windows from the BIOS (found under
System in NT “higher reliability use”).
SAM:- Holds the user names and password hashes for every account on the
local machine, or domain if it is a domain controller.
Software:-Software-specific information and settings.
System:- System startup and device driver information, and operating
system settings.
Network:- Information about networks installed to the machine.
Security:- Network security settings.
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8. HKEY_USERS
Contains the root of all user profiles on the computer.
HKEY_CURRENT_USER is a sub key of HKEY_USERS.
HKEY_USERS
contains
user-specific
configuration
information for all currently active users on the computer.
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9. HKEY_CURRENT_CONFI
This key handles Plug and Play and contains information
G the current configuration of a multiple hardware
about
configuration computer “contains information about the
current configuration of hardware attached to the computer”.
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10. HKEY_DYN_DATA
HKEY_DYN_DATA :- Contains information that must be keep in RAM.
or
HKRY_PERFORMANCE_DATA :- This key provides runtime information into
performance data provided by either the NT kernel itself, or
running system drivers, programs and services that provide
performance data.”
note:- are both services its hidden
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11. Registry Key
Elements
The registry contains two basic elements:-
1. Keys = The registry keys are similar to folder in addition to value
each key can contain sub keys.
2.Values = The registry value are Name / Data pairs stored within keys.
List of standard registry value types:They are normally mean the five main keys.
1. REG_BINARY VALUE
2. REG_DWORD VALUE
3. REG_STRING VALUE
4. REG_MULTI_STRING VALUE
5. REG_EXPANDABLE STRING VALUE
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12. 1. REG_BINARY VALUE = The REG_BINARY VALUE raw binary data, The
most hardware component information is store as binary data and
is displayed in registry editor in hexadecimal format
2. REG_DWORD VALUE = The REG_DWORD VALUE data represented by a
number that is 4 byte long “32 bit integer”. The displayed in registry editor
binary, hexadecimal or decimal format.
a) DWORD_LITLE_ENDIAN “Lowest address”
b) DWORD_BIG_ENDIAN “highest address”
3. REG_STRING VALUE = REG_STRING VALUE is a finite sequence of
symbols that are chosen from set called an alphabet.
4. REG_MULTI_STRING VALUE = REG_MULTI_STRING VALUE that contain
lists or multiple value in a from that people can read are generally this type.
Entries are separated by space, commas or other marks.
5. REG_EXPANDABLE STRING VALUE = REG_EXPANDABLE STRING
VALUE
that can contain environment variable a variable length data string
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13. …?
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14. Than
k
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