Windows multi-boot files

There are more and more friends who are installing multi-boot systems, but few people are fully aware of the role of several important files in a multi-boot system. Let me briefly introduce the author below, I hope that you can pay attention to these documents in the future, in case of need.

Since Windows 95/98/ME (hereafter referred to as Win9X) and Windows NT/2000/XP/Server 2003 (hereafter referred to as WinNT) have different boot methods, Microsoft has adopted a multi-boot system. A very clever way to solve this problem. Win9X uses a direct read boot sector to boot the system, while WinNT uses NTLDR and NTDETECT.COM to boot the system. This is one of the reasons why Win9X is afraid of boot sector computer viruses. It should be noted that in the startup process of the WinNT architecture, there is a file that needs attention. This file is a BOOT.INI file that is often hanged by everyone. Since the importance of this document has been over-enhanced, it has created a false impression that this document is omnipotent, and there have been some "classic" errors. For example, "backing up the dual system boot file only needs to back up the BOOT.INI file in the root directory of the C drive." Actually, in some cases, only backing up this file will not solve the problem. For a detailed explanation, please see the instructions below.

First, the most important five files

This article will analyze the files that play an important role in the multi-boot system, they are the following: BOOT.INI, BOOTFONT.BIN, BOOTSECT .DOS, NTDETECT.COM, NTLDR. Among them BOOT.INI is a configuration file that everyone is very familiar with. From this file, you can choose which operating system to boot from. You can also control the startup mode by modifying the BOOT.INI file. For example, you can use the fast self-test mode by adding the "/fastdetect" parameter to the operating system specifier. Similarly, parameters such as "/nodetect" are available. However, it is not that you can't boot your operating system without this file. The consequence of losing this file is that it can only be booted from the C drive. Also, since this file is a completely text-based file, we can edit it with any text editing tool. In other words, BOOT.INI is not the most important file in the multi-boot system, it can not be said that "backup dual system boot files just back up the BOOT.INI file in the root directory of the C drive."

Friends who are familiar with the startup mode of the multi-boot system know that the startup process of the operating system starts from NTLDR. NTLDR determines the location of the operating system boot partition by reading the BOOT.INI file. For computers with only one operating system, NTLDR starts NTDETECT.COM to start the next startup process. For computers with multiple boot operating systems, NTLDR will display the BOOT.INI selection menu content on the screen for the user to select. It can be seen that NTLDR is the key document for determining the multi-boot system. The common startup error prompt is also: "NTLDR is missing." So what is the use of other files?

NTDETECT.COM is a system-level file used to initialize hardware devices, and then pass the hardware information to the next startup step, and finally complete the operating system. Startup. It should be noted that this file is only stored in the operating system of the NT architecture, and the startup process under Win9X is another way.

The importance of the above three documents has been known to many readers, but the importance of the following documents is probably unknown. This file is a very critical file for starting the Win9X operating system in multiple boot: BOOTSECT.DOS. From the name, I can't see the special use of this file, but if your multi-boot operating system combination contains Win9X, then you can find this file in the root directory of the C drive. This file is not large, only 512 bytes. In fact, this file contains all the data in the boot sector that everyone is very familiar with. How is this file generated? When NTLDR is installed, the installer automatically saves the original boot sector as a BOOTSECT.DOS file and then overwrites the sector with the new boot data. When this file is lost, when you choose to start Win9X, what you see is no longer the familiar blue sky and white clouds startup screen, but a bunch of English prompts on the screen. The translation is the result of I/O error, the system No fa starts. Why is this? Because NTLDR knows from your choice that you will start the Win9X system and then read the BOOTSECT.DOS file to start the Win9X boot process, but since the BOOTSECT.DOS file does not exist, the boot process will of course fail.

Another important document is BOOTFONT.BIN. This file is actually a Chinese font library for displaying in Chinese at startup. Otherwise, you will only see the full screen English prompt.

The above five files are all located in the root directory of the C drive, and all have certain attributes, such as hidden, system, read-only, and so on. To view and modify these files, you need to cancel these special properties first, otherwise your operation will not be able to proceed.

Second, need to pay attention to the problem

NTLDR, NTDETECT.COM two files have backward compatibility, but not upward compatibility, that is, you can use Windows XP The files start Windows 2000, but they can't start Windows Server 2003. This explains why many friends fail to start Windows XP after installing Windows 2000 on a computer with Windows XP installed. The solution fa is actually very simple: remove these two files from the Windows XP installation CD to overwrite the file with the same name on the root directory of the C drive. There is also the BOOTSECT.DOS file that is easy to be ignored by everyone. Once this file is lost or damaged, of course, Win9X cannot be started. The solution fa is also very simple: insert a Win9X boot disk, execute the SYS C: command, and then restart, this time Win9X boot has been restored, just re-run the WinNT installation CD, select repair to restore multiple boot select boot mode .