【 Weak current College 】 save the hard drive of the ten methods

Each user's hard drive is stored with a lot of useful data, but the hard drive is a faulty part in order to effectively save data in your hard disk, in addition to a valid data saved on your hard disk, the backup job, but also learn how to hard disk failure hard drive, or save them to extract useful data, the loss to a minimum.

1. the system does not recognize the HDD

Such a failure of the more common, that is, from the hard drive failed to start, start from a disk or enter the c disk, use the automatic monitoring of cmos function cannot find the hard drive of this fault exists. mostly appears in the connection cable or an ide port on the hard disk itself, the failure rate is very small, to Reseat the hard drive cable or change ide interface and cable, replace the test, you can soon find fault resides. If new connected to the hard drive is not recognized, there is another common reason is that the hard disk's master-slave line, if the hard drive is connected to the IDE's main disk location, then the hard disk you must jump as discoid, jumper errors generally cannot detect the hard drive.

2.cmos troubles

CMOS are correct or not directly affect the normal use of the hard disk, here mainly refers to the hard disk type. fortunately now machines support ideautodetect features, you can automatically detect the hard drive's type. when linking a new hard drive or replace a new hard drive after using this function to set the type of course, there are types of Board can automatically identify the type of hard disk drive type error when, sometimes simply cannot start the system, can sometimes start, but will read and write errors. such as cmos type hard drive in less than the actual capacity of the hard disk, the drive behind the sector will not be able to read and write, if it is a multiple-partition state the individual partitions will be lost. There is also an important cause of the failure, due to the current ide support logical argument type, hard disks can be normal, lba, large ... If in normal mode to install the data, but also in the CMOS to other modes, will occur error the hard drive's read/write failure, because of its physical geology mapping relations have changed, and will not be able to read the original correct hard disk location.

3. the primary boot is causing boot failure

Hard disk's master boot sector of a hard drive is the most sensitive part, one of the primary boot program is a part of it, this program is mainly used to detect the hard drive partition is correct, and to determine the active partition, is responsible for guiding the rights transferred to the active partition dos or other operating system-this section is damaged will not be able to boot from the hard drive, but from the soft area or light area you can then read and write to the hard drive-repair this failure means simpler, high version dos fdisk most convenient, when run with parameter/mbr, will direct replacement (override) the hard drive's master boot program. indeed hard disk's master boot sector is the establishment of this program, which contains fdisk.exe complete hard disk partition program although dos version update, but the hard drive's master boot program has not changed from dos3.x to currently windos95 DOS, so long as a dos boot disk to boot the system and run this program to fix the. Moreover, like other tools software kv300 also has this feature.

4. partition table errors boot boot failure

Partition table errors is the hard drive of a serious error, the extent to which different errors can cause different losses. If there is no active partition labels, the computer will not start. However, from the soft area or light zone boot system can read and write to the hard disk, you can reset the active partition fdisk to repair if it is a partition type error, you can create a partition of partition table is lost-the first four bytes of the value for the partition type, normal bootable is greater than 32 MB basic dos partition value 06, and Extended DOS partition values is essential if the 05. dos partition type to you cannot start the system 05, and will not be able to read and write the data. If 06 to dos unrecognized types such as dos, then view efh changed partitions is not a dos partition, of course, cannot read and write-many people exploit this type value for a single partition encryption technology, restore the original value of the correct type to make the partition back to normal. partition table of other data is used to record partition of the start or end address these data damage will result in the confusion or loss, generally cannot be manually restored, the only way is to use backup of partition table data writeback, or from another of the same type and partition of the same hard drive gets a partition table data, otherwise will result in additional data is permanently lost. in the master boot sector for the operation, you can use tools such as software, nu operation is very convenient, can be directly on the hard disk partition boot sector for reading or writing or editing, of course you can also operate using debug, but cumbersome and have a certain risk.

5. the partition is valid flags errors hard drive failure

In the hard disk partition boot sector is also an important part, that is, the last two bytes: 55aah, this word is the sector's valid flags. from your hard disk, floppy disk or optical area startup, will detect these two bytes, if there is considered to have a hard drive exists, otherwise it will not recognize the hard drive. This flag when you boot from the hard drive will turn into rombasic or tips in the floppy from the floppy disk boot-cannot be transferred to the hard disk. here can be used for whole disk encryption technology-use debug method of recovery processing. Furthermore, the dos boot sector still has this flag is present, when a dos boot sector without boot flags, system startup is displayed as: missingoperatingsystem. the repair method can be used in the master boot sector repair methods, only the address of a different, more convenient way is to use the following dos system generic fix.

6.dos boot system from a boot failure

Dos boot system is mainly composed of dos boot sector, and the dos system files.System files including io.sys, msdos.sys, command.com, which is a dos shell command.com files, available to other similar files replace, but by default is the must-dos boot file in the dos system windows95, msdos.sys is a text file, start the Windows must file only boot dos, however, may need this file, but an error, the dos boot from floppy disk or CD to boot the system, after using sysc: delivery system to repair failures, including the boot sector and system files can be restored to normal.

7.fat table reading and writing faults caused by

Fat table records at hard drive data storage address, each file has a set of connection of the fat chain specifies its storage cluster address .fat table corruption means that the contents of the file is missing. Fortunately dos system itself provides two fat tables, if you currently use fat table is damaged, use the second to cover repair-but because of the different specifications of disk its fat table length and the second fat table of addresses is not fixed, so you must find the correct while repairing their correct location, some tools software such as nu, itself has such capability, using very convenience. using debug can achieve this kind of operation, that is, with its m command the second fat table moves to the first table, then if the second fat table is corrupted, you cannot put the hard disk to restore to its original state, but the file still resides in the data in the data area of the hard disk, you can use chkdsk or scandisk command to repair, the resulting * the .chk file, this is the loss of fat chain sector data. If is a text file you can extract and merge complete file, if it is binary data files, it is very difficult to recover complete file.

8. the directory table corruption causing boot failure

Directory table records at hard drive data such as file names, one of the most significant is the start of the file, the directory table because of the family does not have an automatic backup function, so if a directory is damaged you will lose a large number of files-a method of reducing losses also use chkdsk or scandisk above program method, search the hard drive out of the chk file, the directory table corruption is the first family loss, fat is damaged the chk files generally relatively complete file data, each a chk file that is a complete file, put it to the original name to recover most of the file.

9. when data accidentally deleted partition recovery

When using fdisk delete hard drive partitions, the surface is hard disk's data has been completely disappear, when access to the hard disk is unformatted display invalid drive. If you know fdisk works, you'll know that fdisk just rewritten the hard disk's master boot sector (0-0 Road 1 slice) content-specifically deleted hard disk partition table information, and any partition on your hard disk data is not changed, you can copy the partition table error fix, i.e. to recover partition table data to restore the original partition the data, but this is limited to subject to partition or rebuild partition after the partitioning if already formatted with the format, the first recovery partition, in the following methods to restore partition data.

10. wrong format the hard drive data recovery

In the dos version State, format operation format in the default state is established to restore formatted disk information, actually put the disk DOS boot sector, partition table and fat list of all of the content is copied to a disk in the last several sectors (because subsequent sectors are rarely used), and the data area of the content has not changed. This can be by running unformatc: restore the original file allocation table and table of contents, thus complete hard disk information recovery. dos also provides one miror command is used to record the current disk information for formatting or deleting the recovery after use, this method is also more effective.