Common Fault Analysis and troubleshooting for hard drive failures

As the most important storage device of a microcomputer, hard disks play an important role in the microcomputer system. If the hard disk cannot be started, it will cause you to be in a hurry. Here we will introduce you to several "weapons" to specifically deal with the "stubborn" problem that hard disk cannot be started. You must be careful when using them. Otherwise, if the hard disk is damaged, the silver will be wasted!

Fault symptom 1: "device error" is displayed on the screen after the instance is started, and "non-system disk or disk error, replace and strike any key when ready" is displayed ", the hard disk cannot be started. After the disk is started with a floppy disk, enter "C:" After a: \> and the screen displays "invalid drive specification". The system does not recognize the hard disk.

Fault Analysis and Handling: the cause of the fault is generally caused by the loss of hard disk setting parameters in CMOS or incorrect hard disk type settings.

Go to CMOS and check whether the hard disk setting parameters are lost or whether the hard disk type is set incorrectly. If this is the case, you only need to restore or modify the hard disk setting parameters. If you forget the hard disk parameter, you can also use the backed up CMOS information for recovery. If you have not backed up the CMOS information, do not worry. Some high-end microcomputer CMOS settings have the "HDD Auto Detection" option, hard Disk type parameters can be detected automatically. If this option is not available, you have to open the chassis, view the hard disk parameters on the hard disk surface label, and modify the parameters accordingly.

Fault symptom 2: After the instance is started, the "wait" prompt will be stuck for a long time, and the "HDD controller failure" will finally appear ".

Fault Analysis and Handling: the fault is generally caused by poor contact with the hard drive line interface or wrong wiring. Check the connection between the hard disk power cord and the hard disk, and then check the connection between the hard disk data signal line and the multi-function card or hard disk. If the connection is loose or the connection is reversed, the above prompt will be displayed, it is best to find a computer with the same model and normal use. You can compare the connection of the cable. If the cable is reverse, it will be clear at a glance.

Fault symptom 3: After the boot, the screen displays "invalid Partition Table". The hard disk cannot be started. If the disk is started from a floppy disk, the C disk is recognized.

Fault Analysis and Handling: the cause of the fault is generally that the partition table in the hard drive Master Boot Record has an error. When multiple auto-cited partitions are specified (only one auto-lifted partition can exist) or when the virus occupies a partition table, the above prompt is displayed.

The Master Boot Record (MBR) is located in the 0 head/0 cylinder/1 sector and is generated when fdisk. EXE partitions hard disks. MBR includes Master BootProgramThe partition table and the ending sign 55aah constitute a single sector. The main boot program contains a program to check the hard disk partition table.CodeAnd error information, error handling, and so on. When the hard disk is started, the main Bootstrap will check the auto-lifting flag in the partition table. If a partition is a custom partition, it indicates 80 h. Otherwise, it is 00 h. The system requires that only one partition be a custom partition, if the partition table contains multiple auto-raising marks, the primary Bootstrap will prompt "invalid partion table. The simplest solution is to use NDD to fix errors in the partition table. If an error is found, you will be asked if you are willing to modify the error. You only need to continuously answer yes to correct the error, you can also use the partitioned table that has been backed up to overwrite it (kv300 and rescue in nu8.0 all have the function of backing up and restoring the partitioned table ). If the partition table is infected with virus, the problem cannot be solved by formatting. You can use anti-virus software and NDD to fix the problem.

If none of the above methods can be solved, another way is to use fdisk to re-partition, but the partition size must be the same as the original partition. This is especially important. Do not perform advanced formatting after the partition, then use NDD to fix the problem. The recovered hard disk can be started, and the information on the hard disk will not be lost. In fact, using fdisk partitioning is equivalent to overwriting the original partition table with the correct partition table. This trick is especially effective when the hard disk is not recognized after a floppy disk is started.

Fault symptom 4: After the system is started, the self-check is completed. When the hard disk is started, the system crashes or the screen displays "no rom basic, system halted ".

Fault Analysis and Handling: the cause of the fault is generally caused by damage to the boot program or virus infection, no self-lifting mark in the partition table, or the end mark 55aah is rewritten. Start from a floppy disk and execute the command "fdisk/MBR. Fdisk contains the main boot program code and the ending sign 55aah. With the above command, the correct primary boot program and ending sign in fdisk can overwrite the primary boot program on the hard disk, this action is fast and flexible for fixing the master boot program and ending sign 55aah damages. NDD can be used to quickly recover a fault that does not have a self-lifting flag in the partition table.

Fault description 5: After the instance is started, the system prompts "error loading operating system" or "missing Operating System" appear on the screen.

Fault Analysis and Handling: the fault is generally caused by an error in the DOS Boot Record. The dos Boot Record is located in the logic 0 sector and is generated by the advanced format command. After checking that the partition table is correct, the main Bootstrap program reads the DOS Boot Record Based on the start address of the DOS partition specified in the partition table. If five consecutive reads fail, the error message "error loading opearting System" is displayed. If the DOS boot record can be correctly read, the Main Boot Program will send the DOS Boot Record to the memory at 0: 7c00h, then, check whether the last two bytes of the DOS Boot Record are 55aah. If not, the system prompts "missing Operation System. You can fix it with NDD. If it fails, you have to use the format C:/s command to overwrite the DOS Boot Record. Maybe you will think that the data on drive C will be lost after formatting. In fact, you don't have to worry about it. The data is still stored on the hard disk, after the drive C is formatted, unformat in nu8.0 can be restored. If you have used the mirror in the doscommand or the image program in nu8.0 to create an image file for the hard disk, the hard disk can be completely restored. Otherwise, all files in the root directory of the hard disk are lost, the first sub-directory name under the root directory is changed to dir0, dir1, dir2 ......, However, the files under the first-level sub-directory and their sub-directories are intact. For the files lost under the root directory, you can use the unerase in nu8.0 to restore them.

In summary, the failure to start a hard disk is mostly due to the error of the Master Boot Record, DOS Boot Record, and three hidden files on the hard disk, therefore, we need to develop a good habit of backing up the Master Boot records and DOS boot records, so that the problem can be solved smoothly at critical moments.