Hard Disk Errors Are You Responsible

A mobile computer's hard drive is most vulnerable to movement during the power-down sequence. Use the sleep mode to avoid some hard disk problems.

Hard drives store data in files on most computer systems. As Andy Coates (2008) has pointed out, a hard drive contains a rotating platter which has a magnetic coating. Data is stored and retrieved by a read/write head which is positioned over one of the platter's numerous circular tracts. The rotation of the platter positions the appropriate data storage area under the read/write head, and the data is transferred.

Recovering From Read Errors

A Cyclic Redundancy Check (CRC) is stored with every data chunk on the hard disk. A CRC is like a sub-total, a checksum in computer jargon; but the CRC is calculated by a complex formula, which minimizes the chance that multiple errors would allow corrupted data to be accepted. When a read error is encountered, the computer system rereads the data; and most read errors go unnoticed by the user.

Hard Drive Write Errors

If data are incorrectly written to the hard disk, the computer will later refuse to accept the adulterated information. Multiple clicks are often heard as the system attempts to retrieve bad data. A corrupted file cannot be used, but several services are available to help recover the damaged data.

How Do Hard Disk Errors Happen?

If a laptop or notebook is jarred from the side while it is in the act of transferring data to the hard disk, the write head can be displaced onto an adjoining tract (Anonymous, 1994). The drive will continue writing data, but in the wrong place.

If the displacement of the write head occurs over an empty portion of the hard disk, no damage is done. However, if the write head is moved over a previously stored file, the older file is corrupted (Anonymous, 1994). The error may become apparent only when the computer attempts to retrieve the ruined file.

I Don't Whack the Computer When I Press Save!

When a user clicks the save icon or closes an application, the computer writes data to memory rather than to the hard disk. This information is transferred to the disk as time allows; but some data usually needs to be stored when the laptop or notebook is turned off. Consequently, several seconds are needed; and during this short interval, the computer is most vulnerable to hard disk corruption. Once a user has started the power-down sequence, he should not move his computer until that sequence has completed.

But I Have To Move My Laptop/Notebook Right Now!

Emergencies can force a user to relocate his computer. A supervisor says, “Follow me and bring your computer.” A toddler gets into; well, what doesn't a toddler get into? The 30-seconds to let the computer completely power-down is simply not available.

Closing the Lid Options

In Window's Control Panel, the user can select what actions the computer takes when the lid is closed. This writer advises placing the computer into the sleep (not hibernate) mode. The sleep mode is simply a low power state, and nothing is written to the hard drive. The user can select whether a password is required when the computer is brought out of the low-power mode.

In conclusion, some hard disk errors can be avoided by having the computer enter a low-power state when the lid is closed. This allows the computer to be moved quickly and safely. Hard drive errors can also be minimized by making certain that the computer has completed its power-down sequence before it is moved.

This article from Dreamyoup