| Computers are very fickle machines, as we all | | | | and is wearing on the disk. 5) Spurious bad |
| know, they can be sturdy and reliable in the most | | | | sectors. |
| trying times. You can drop them and kick them | | | | Another hard disk defect is gradual disk failure. |
| and spill coffee all over them and they won't be | | | | When a certain sector in your computer becomes |
| fazed at all and one day an ant will crawl on top | | | | unreadable its contents are copied to a spare |
| of it, there will be a click, a buzz and your screen | | | | sector (one of many that your computer has) |
| will beat a hasty retreat. The causes of data | | | | and retains its physical sector address. This |
| corruption are rich and varied, it could be all the | | | | process is completed before the sector has failed |
| kicking and the dropping and the coffee spilling, or | | | | completely. Once the sector can no longer be |
| it could be any one of the following: | | | | read then it is possible that silent data loss can |
| Bad exits from Windows. There are several | | | | occur. Only when all the spare sectors have been |
| conditions under which this occurs e.g. if the user | | | | used up or when a defect is too severe to be |
| switches the computer off or resets it without | | | | repaired, all of the bad sectors will become visible |
| shutting down properly, if the shutdown process | | | | to diagnostics. It is therefore preferable to replace |
| fails in some way, if there is a power cut and the | | | | the first bad sector while it is still under warranty. |
| computer resets on its own or if the computer | | | | Other flaky hardware. If something is capable of |
| freezes or locks up so that shutdown is | | | | corrupting the data in RAM, it is capable of |
| impossible. This type of crash is usually in | | | | corrupting the hard drive contents. Examples of |
| accordance with sane file management; therefore | | | | this include: 1) bad RAM 2) bad processor fan 3) |
| the only data corruption observed will be the | | | | over-clocked PCI bus 4) Data cables that are too |
| interruption of sane file operations. The only | | | | long or too old or generally in a bad condition 5) |
| damage visible should be incorrect free space | | | | overheated or poorly grounded hard drive 6) |
| count, lost cluster chains and possible incorrect file | | | | flaky motherboard, hard drive controller and |
| lengths. | | | | processor. Failures of theses kinds can result in |
| Hard drive disk defects. Hard drive failure comes | | | | corrupting what is written to the disk as well as |
| in various guises: 1) sudden catastrophic failure, | | | | corrupting where things are written to the disk. |
| which occurs when a drive can no longer be seen | | | | Neither of these is particularly good news to a |
| by its operating system. This kind of failure | | | | computer owner. |
| requires clean-room facilities and expert know | | | | It is recommended to try and prevent the pain |
| how in order to repair it. 2) Head crash - heads | | | | and hassle of hard drive corruption by running a |
| touching and damaging the surface of the disk 3) | | | | disk defragmenter every 3 months to keep it in |
| pollution of the air inside the sealed drive unit 4) | | | | good condition. In addition to this you should try |
| general surface wear often goes hand in hand | | | | to move your computer as seldom as possible. If |
| with pollution of the sealed air inside the drive unit. | | | | you have to move it, it is best to repack it in its |
| It could be that the air filters malfunction or seal | | | | original packing materials to protect it during the |
| up or it could be that the unit was opened; | | | | move. Remember to back up your data on a |
| perhaps debris was spread during a head crash. | | | | regular basis and lastly, and very importantly, |
| Whatever the reason, dirt has got into the unit | | | | don't drop it. |