A feature of PC and its operating system is that it allows users to configure the hardware and software of computer system in various ways according to their own requirements. In early graphical operating systems, such as Win3.x, the configuration of software and hardware working environment was completed by modifying files with extension. INI, but the management of INI file is very inconvenient, because each device or application has its own ini file, so it is difficult to achieve remote access on the network.

In order to overcome these problems, in Windows 95 and its subsequent versions, a database called "Registry" is adopted for unified management, which centralizes all kinds of information resources and stores all kinds of configuration information. According to this principle, a registry containing all configuration information of application programs and computer systems is adopted in all versions of Windows to manage the association between application programs and files, the description of hardware devices, status attributes and various status information and data.

Unlike the INI file:

1. Registry logs in data in binary form;

2. The registry supports subitems, and subitems at all levels have their own "key values";

3. Entries in the registry can contain executable code instead of simple strings;

4. On the same computer, the registry can store the characteristics of multiple users.

The characteristics of the registration center are:

The 1. registry allows you to track the configuration of hardware, system parameters, applications and device drivers, which allows you to modify some settings without restarting.

2. The hardware data registered in the registry can support the plug-and-play function of a higher version of Windows. When Windows detects a new device on the machine, it will save the relevant data in the registry. In addition, the resource conflict between the new equipment and the original equipment can be avoided.

3. Managers and users can view the configuration and settings of the system on the network through the registration form, so as to realize remote management.

Complete Registry Recovery Manual

The registry appeared in front of us as Win95, in fact, it has long played an important role in nt. The main purpose of using registry to manage system configuration is to improve system stability. And some problems in the system (such as unable to start, unable to run applications, abnormal system work, etc.). ) are mostly caused by registry errors. By modifying the corresponding error data, Windows can work as before. However, the structure of the registry is too complicated, and incorrect modification will often bring worse results. Here are several ways to safely restore the registry, hoping to help you stay away from troublesome registry problems.

Misunderstanding of rainless silk

And various information to be called when using a large number of applications. It consists of three relatively independent registry files: system configuration registry file: system.dat, user platform configuration registry file: user.dat and network management registry file: config.pol. They are stored in the Windows directory, in which system.dat stores the current computer configuration, especially the hardware configuration of various plug-and-play devices, such as I/O address, interrupt number (IRQ) and DMA value. User.dat is mainly used to define the priority of users and store the installation information of user-specific applications. Config.pol is a registry file, which will only be generated when users of Win98 install the system policy editor, and its stored settings can restrict the operation of network users. Generally speaking, two files, system.dat and user.dat, are essential to form a complete registry file system.

First, file backup and recovery methods

Obviously, timely and correct backup can completely restore the whole working process when the computer has an accident. The same is true for the backup of the registry. The backup registry under normal working condition can be used to restore the wrong registry, so as to restore the normal work of the system.

(1) backup

1? Simple replication method

Backing up the registry means backing up the two files, system.dat and user.dat. Their file attributes are systematic, hidden and read-only, so they are generally invisible under DOS Windows windows, so we should pay attention to using some "technologies" when backing up.

In DOS state, please enter the Windows directory first, and then enter the command "Attrib -h -r -s system.dat. Dat". Do the same for user.dat, and then you can copy these two files to other directories.

In the state of Windows window, select folder option → View in View, and select Show all files in hidden files, so that system.dat and user.dat can be displayed in the folder window. I don't need to say much about the rest of the copying work.

2? Registry export method

Exporting the registry is also a good way to back up the registry. Run Regedit.exe in the Start → Run bar, select Registry → Export Registry, and finally select the storage location of the exported registry file. It should be noted that when exporting the registry, you must select all registry keys within the export range, otherwise the exported registry file is incomplete and will not be used to restore the original registry. Only one file is generated after backup in this way, and the suffix of its file name is. Register.

(2) reduction

1? Simplified replication method

Of course, the recovery method is to overwrite the existing files with the backed-up files. However, it should be noted that before overwriting the existing files, the file attributes of system.dat and user.dat must also be completely canceled, otherwise the system will reject the overwrite operation. Be sure to boot to DOS before recovery, and then do this operation. Never perform this recovery operation under Windows or Windows DOS window, otherwise the registry will not be recovered, but will be greatly damaged.

2? Recovery of registry export method

When using the registry export method to restore the registry file system, it can be done under Windows or DOS.

In Windows, after running the registry, select Registry → Import Registry, and select the location of the registry file to be imported. After a reboot, the registry can be restored. Although this method can be carried out in both safe mode and normal mode, for the sake of safety, the author still suggests that it is best to operate in safe mode or simply in DOS, as described below.

Under DOS, Regedit.exe can only run through the command line, but it can solve the problem of registry recovery when Windows is inaccessible. Its command line form:

regedit[/L:system][/R:user]filename 1

regedit[/L:system][/R:user]/C filename 2

regedit[/L:system][/R:user]/E filename 3 regpath 1

regedit[/L:system][/R:user]/D regpath 2

Parameter meaning:

/L: system specifies the storage location of the system.dat file;

/R: user specifies the storage location of the user.dat file;

Filename 1 specifies the file name of the imported registry database;

/C filename2 Regenerates the registry with the specified registry file;

/E filename3 exports the registry file to the specified file name;

Regpath 1 Export the specified start keyword from the registry file;

/D regpath2 Deletes the section that specifies the start keyword from the registry file.

Specifically, when restoring the registry, you can use the command line 1: Regedit bak.reg (assuming that the exported backup registry file has this file name). However, it is suggested to use command line 2, i.e. Regedit /C bak.reg, because this command will not only import all the information in bak.reg into the registry, but also delete some useless information (such as the residual keywords of some deleted programs in the registry), so as to achieve the purpose of compressing and rebuilding the registry.

By the way, you don't have to use command line 2 until the registry is restored. You can also compress and clear the "garbage" in the registry during normal operation, thus improving the startup speed of Windows and reducing the probability of registry errors. The author once used this command to compress the original 6 MB registry into 4 MB. It should be noted that when using this command, please be sure to load the disk buffer smartdrv before running, otherwise it may run long enough for you to watch movies!

Second, the system backup method

It is precisely because of the importance of the registry to the system that Microsoft considered the automatic backup of the registry when developing Win95. Although the function it provides is not satisfactory until Win98, it is one of the ways to repair the registry after all.

windows 95

At the beginning, the method of automatically backing up the registry provided by the system in each version of Win95 was relatively simple, and the current registry file was usually backed up at the same time when the Windows system was started. The specific method is to back up two files, system.dat and user.dat, as system.da0 and user.da0 with the same attributes respectively. Therefore, when the system can't start due to the damage of the registry, you can manually copy the two files, system.dat and user.dat, and overwrite them (please note that the file attributes of these four files are cancelled before the operation). Although this idea is good, due to negligence and some unforeseen circumstances, the registry automatically backed up by the system will often be destroyed unconsciously or the backup will fail. For example: ① When the registry is damaged on the Internet.

It happened before the last shutdown. When you start the system again, the backup registry is actually a "complete" copy of the damaged registry. (2) The registry is correct at startup, and the registry automatically backed up by the system is also good at this time. However, unexpected circumstances (such as sudden power failure, unexpected hard disk reading and writing errors, etc.). ) will cause the system to fail. When you start again, the original full registry backup will also be overwritten by the damaged registry. Therefore, the effect of using two backup files, system.da0 and user.da0, to restore the registry is not ideal, and the success rate is generally around 50%. Be careful not to try to start again after the startup fails. You should immediately overwrite the recovery with two files, system.da0 and user.da0, otherwise more than 90% of the systems will never be recovered.

windows98

Win98' s improvement on the registry file backup system is mainly reflected in the following two aspects: ① The backup file includes not only system.dat and user.dat, but also two initialization files, namely system.ini and win.ini, which greatly improves the integrity of system recovery; ② The backup files are uniformly compressed in one file, which greatly increases the number of backup compressed files, and avoids the phenomenon that Win95 is prone to make mistakes and cannot be recovered in the next backup.

Win98 puts the backup file of the registry in the hidden subdirectory Sysbckup under Windows. Backup files are compressed files in CAB format named rbX, and each file contains system.dat, user.dat, system.ini, win.ini By default, the system * * * has five compressed packages for backup (x is from 000 to 004, and if there is an error once, the numbers will be postponed later). These five compressed package backups were made by the system when you first started your computer in the last five working days. Please note that it is not the last five times. For example, if you use your computer every day, five backups will save the registry file when you first start your computer for five days. When a startup error occurs, the system will save the registry file as rbbad.cab for users to analyze and find out the cause of the error.

After understanding the backup principle of Win98, it is easier to restore the registry. If you can enter Windows (even in safe mode) and want to make backup and recovery, you only need to use software supporting CAB compression format, such as Winzip, select the backup compressed package files of recent or previous days, extract four of them, restart the computer to DOS state, and overwrite the corresponding files with these files. If you can't access Windows at startup, you can try to do backup and restore under DOS: ① Use the extract.exe file provided by Windows, expand the backup file through the command line, and directly overwrite the restore system registry file (assuming the current directory is Windows): extract/y? . ? Sysbckup\ rbX.cab, where x is 000 ~ 004. (2) Use the scanreg.exe that comes with Windows to run this program in DOS state, and choose to view the registry according to the prompt. After the program checks the registry, you can see creating backups and viewing backups. The former is used to back up the current registry, and the latter is used to view the previously backed up registry. Select the latter, and the screen will display the registry files backed up in recent days (mainly the backup time). Select the backup to Restore, press Enter, and then select Restore to start the restore. After recovery, select Restart to restart the computer.

Note: When you fail to start the computer for the first time, please don't continue to try to start the computer, because scanreg.exe will back up all the failed registries one by one. If you fail to start the computer five times in a row, it means that the five good registries that were originally backed up will be replaced by five bad registries in a row, and you will lose the opportunity to use them to restore the system registry. So after the startup fails, please try not to restart it repeatedly and restore the registry in time.

Mend a dead sheep

As the ancients said, it is not too late to mend. If you have never been used to backing up the registry, or all automatic system backups under Windows have been replaced by the damaged registry files mentioned above, then try the following methods, which may make your machine work normally again.

A, conservative reduction method

Generally speaking, after the successful installation of Win9X, the system information (in fact, the registry information, mainly the corresponding hardware information) of the first normal operation will be automatically saved in the file system. 1st under the root directory of drive C.. With it, the system can be restored to its original installation state. The specific method is as follows: Under DOS, first delete the file attributes of system. 1st and system.dat in the Windows directory (both are system, read-only and hidden attributes), and then copy the system. 1st to overwrite system.dat, and finally restart the computer. If the startup is successful, the system will have to be greatly adjusted to restore the state before the destruction.

Second, the "Li Jiang" method

If there is a computer with roughly the same hardware configuration as yours, you can overwrite the registry file on your computer with the registry files (system.dat and user.dat) on that computer, and then start it. If you can enter Windows, and then modify the system accordingly, you can return to the previous appearance. Although the probability of success of this method is relatively small (about 25%), it is a last resort and may really save your "dead horse as a living horse doctor".

If the above tricks don't work for you, then I'll teach you another "super trick"-prepare your Windows installation CD and install it! Based on my understanding of the registry (which is often modified) and the above-mentioned tricks, the author has created a new personal record. Win98 was installed in June last year and has not been reinstalled in 5438+ 10.

How to clean up the registry

Delete redundant dlls and other files.

Friends who are interested in * * * software may all know the famous DLL file cleaning tool CleanSweep. Its function is to delete a large number of useless DLL files left in the system directory when we add or delete programs in the system for a long time, thus improving the working efficiency of the system and reducing the loss of hard disk space. Through the registry, we can also find some useless DLL file information or VxD file information and delete it, thus improving the operating efficiency of the system: open "HKEY- Local-Machine \ Software \ Microsoft" in the registry in turn.

\ Windows \ Current Version \ Share DLL ",the items contained under this sub-item are the information of DLL files written into the registry after the application is installed, and the key value of each DLL file indicates * * * the number of applications that enjoy this DLL file (when uninstalling these applications, the uninstaller will give something like" xxx file is shared by other files * * *, are you sure you want to delete it? ), if the corresponding value of a DLL file is 0, it means that this DLL file is useless to the system and we can delete it directly. For other types of files, as long as their values are 0, we can judge that they are useless and should be deleted.

In addition, under this sub-item, you may find that many files deleted before include many files contained in the folder (no longer exists on the hard disk), and their values are not necessarily 0, but you can delete them completely.

Reconstruction and clean-up

We know that all kinds of undeletable uninstaller information in "Add or Remove Programs" can be deleted through the registry, so have you ever thought that when you add or delete a large number of applications and hardware device drivers, you will inevitably write data into the registry? After a long time, these discarded data will become more and more, and your registry file will become more and more bloated, which will not only make your "bar" slower and slower because of the increasing burden, but also often lead to an inexplicable strike or prompt error.

Now, let's start to delete this useless information by rebuilding the registry. First, open the registry editor, and click the "Export" command under the "File" menu in the registry editor to export the existing registry containing various software and hardware resources, and give it a name, such as dc 1.reg (it is best not to give it a Chinese name, because it is necessary to rebuild the registry under DOS).

Then restart the computer to enter the DOS state (DOS mode in Windows 98 cannot be used, and Windows 98 cannot run when the registry is rebuilt), and then execute the following command;

Regedit/c DC1.reg (there should be a space between c and the file name).

Regedit/c means to regenerate the entire registry from a file specified later. After completion, start the computer to enter Windows 98, and you will find that the reconstructed registry file is much smaller than the original (depending on the number of programs installed and uninstalled after Windows 98 installation). After losing weight in this way, the running efficiency of Windows 98 will be improved.

But it should be noted that when rebuilding the registry in this way, you must pay attention to the version of DOS. The average computer only has Windows 98 installed, so there is no problem. If the computer has multiple operating systems installed at the same time, it is best to do this under DOS 7.0, or at least DOS 6.22. It takes a long time for Windows 98 to rebuild the registry. Take my computer as an example, Celeron 300A, upgraded BH6 motherboard, 64M PC 100 memory, quantum fireball 7-generation 6.4G hard disk. The exported registry size is 5.86M, and it takes about 1 hour to rebuild the registry. So before doing this operation, friends had better load the disk cache program Smartdrv to speed up the processing.

Clean up the software information junk in the registry

Although most of the software based on Windows 98 now has its own uninstallation program or provides uninstallation information for the "Add/Remove Program" of Windows 98, they unconsciously deleted themselves when exiting the historical stage, and most of them will not delete the relevant information files in the registry when uninstalling (these information are mainly related manufacturers, ID numbers, user names, etc. When the software is initially installed, it is written in the registry), which leads to the growing size of the registry and more and more useless software information junk. We can manually delete this useless information in the registry:

Open "HEKY-CURRENT-USER \ SOFTWARE" in turn in the registry, and the primary key contained under it is generally named after the software manufacturer. For example, a series of software produced by Microsoft are included in the "Microsoft" primary key item. If you are sure that a software has been deleted, you can delete all its key values.

Start → Run → Command Set!

Winver- check the Windows version.

Wmimgmt.msc-Open Window Management Architecture (WMI).

Wupdmgr-windows updater

Wscript-windows Script Host Settings

writting tablet

Winmsd- system information

Wiaacmgr-Scanner and Camera Wizard

Winchat-XP comes with LAN chat.

Mem。 Exe- displays memory usage.

Msconfig.exe- System Configuration Utility

Mplayer2-Simple widnows Media Player

drawing board

MSTSC- Remote Desktop Connection

Mplayer2-Media Player

Magnifying glass tool

MMC- Open the console.

Synchronization command

Check DirectX information.

Drwtsn32-System Doctor

device manager

DFRG。 Disk defragmenter

Diskmgmt.msc-disk management tool

DCOMNFG- open the system component service.

DDE sharing-open DDE*** to enjoy the settings.

Dvd player -DVD player

Stop the messenger service.

Start messenger service.

Notepad-Open Notepad.

NSLookup- Network Management Tools Wizard

Ntbackup-system backup and restore

Narrator-screen "Narrator"

Ntmsmgr.msc-mobile storage manager

Ntmsoprq.msc-Mobile Storage Administrator Operation Request

Netstat-an-(tc) command to check the interface.

Create a briefcase

System configuration editor

File signature verification program

Sndrec32-recorder

Shrpubw-Create a * * shared folder.

Secpol.msc-local security policy

Syskey-system encryption, once encrypted, it cannot be unlocked, which protects the double password of windows xp system.

Services.msc-local service settings

Sndvol32-Volume Control Program

Sfc.exe system file checker

Sfc /scannow-windows file protection

Tsshutdn-60-second countdown shutdown command

Tourstart-xp xp introduces XP (roaming XP program after installation)

Taskmgr- task manager

Eventvwr-Event Viewer

Eudcedit- word formation program

Browser-Opens the browser.

Packager-Object Packaging

Perfmon.msc-computer performance monitoring program

project manager

Regedit.exe Registry

Rsop.msc-group policy result set

Regedt32-Registry Editor

Rononce-p- 15 seconds off.

Regsvr32/u *。 Stop running the dll file.

Zippfldr. dll-Cancel postal code support.

Rundll32.exe shell32.dll, display control panel.

Rundll32.exe shell32.dll, control _ rundllaccess.cpl and 1-show accessibility options.

Rundll32.exe shell32.dll, control _ rundllsysdm.cpl @1-Open the system properties.

Rundll32.exe shell32.dll, control _ rundllappwiz.cpl, 1- Delete or add programs.

Rundll32.exe syncui.dll, create a briefcase on the desktop.

Diskcopy.dll, Rundll32.exe, disk copy rundll- copy floppy disk drive.

Shell32.dll, Rundll32.exe, controls _ rundlltimedate.cpl, 0- displays the time attribute.

Shell32.dll, Rundll32.exe, controls _ rundlldesk.cpl, 0- displays desktop wallpaper properties.

Rundljoy.cpl, control _ rundlljoy.cpl, 0- game controller.

Rundll32.exe shell32.dll, control _ rundllmmsys.cpl,, 0- audio attribute.

Cmd.exe command prompt

Chkdsk.exe-Chkdsk disk check

Certmgr.msc-certificate management utility

Calc- start the calculator.

Charmap- Starts the character mapping table.

Cliconfg-SQL SERVER client network utility

Clipbrd-clipboard viewer

CONF- start a network conference.

Master of Computer Management

Cleanmgr-garbage disposal

Ciadv.msc-indexing service program

OSK- Open the on-screen keyboard.

Odbcad32-ODBC data source manager

Oobe/msoobe/a- check whether XP is activated.

Lusrmgr.msc-local users and groups

Logout-Logout command.

Iexpress-Trojan binding tool, the system comes with it.

Nslookup-IP address detector

Fsmgmt.msc-*** * Enjoy the Folder Manager

Utliman-Assistant Tool Manager

Gpedit.msc-group policy