Registry: it is hierarchical database which contains information of software /hardware and user profile setting .
Files responsible for making registry:
1)user.dat
2)system.dat
User.dat:this file is responsible for updating user information in registry.
System.dat: this file is responsible for updating hardware /software information in the registry.
How to open registry:
Start—run—regedit.
Registry structure:
Registry is made up of hives.
There are six hives:
1)HKEY_CLASSES_ROOT
2)HKEY_CURRENT_USER
3)HKEY_LOCAL_MACHINE
4)HKEY_USERS
5)HKEY_CURRENT_CONFIG
6)HKEY_DYN_DATA.
HKEY_CLASSES_ROOT:—THIS HIVE CONTAINS INFORMATION ABOUT PROGRAM ASSOCIATED WITH FILE TO OPEN.
HKEY_CURRENT _USER:–THIS FILE CONTAINS INFORMATION ABOUT USER WHO IS CURRENTLY LOGGED ON .
HKEY_LOCAL_MACHINE:—THIS HIVE CONTAINS INFORMATION OF ALL HARDWARE AND SOFTWARE.
HKEY_CURRENT_ CONFIG:–THIS FILE CONTAINS INFORMATION CURRENT HARDWARE PROFILE LOADED
HKEY_USERS:–THIS FILE CONTAINS INFORMATION ABOUT DEFAULT USERS.
HKEY_DYN_DATA:–THIS FILE CONTAINS INFORMATION ABOUT PROGRAMS WHICH ARE LOADED INTO MEMORY ALWAYS.
how to restore registry:
scanreg:this is a registry tool which is used to restore registry
of previous dates
how to use this command:
1)open the computer in dos mode:
2)scanreg /restore.
3)select the date.
how to export or import registry:
start–run –regedit—registry—export/import.