Bill Williams (IT): Support Site
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By BEWARE: Do not throw out your old computers.
Bill Williams

Edit MessageUploaded - 14 Aug 2006 20:03


Do not throw out your old computers, without first being absolutely sure that you have wiped its hard disk clean, with a really secure wiping program.

The BBC is right at this moment showing a TV program of how computers from council dumps are ending up in Africa, notably Nigeria, where the hard disks are often read by criminals who look for personal information, passwords, and bank accounts etc.

Some criminals then raid the bank accounts or blackmail the original owners.

Quite frankly it is simplest to simply remove the hard drive from the computer unit and KEEP the hard drive with all your other critical private documents. Or have great fun and smash the hard drive with a sledgehammer.

If the computer is still working you can get software which you make up as either a bootable floppy or a bootable CD which will do a thorough wipe. It writes all over every data sector of the disk with random numbers and repeats the process five or six or more times with different random numbers. This tend to prevent even the FBI forensic devices from getting anything back from the original data.


A simple Format operation merely wipes the directory, leaving the data in place. An UNFORMAT program can often rebuild the directory and make the files readable again.

Some FORMAT programs include a full disk write-check, this wipes the disk of data, but old data can still be read by forensic devices (the platters are taken out of the drive and mounted in a forensic reader).


Revised on 15 Aug 2006

Bill Williams

Edit MessageUploaded - 15 Aug 2006 14:22

How to identify the Hard Drive.

In desktop computers it is inside the system unit and is a metal box measuring about 4 inches by 6 inches by 1 or 2 inches thick. It has a flat cable connecting into it and also a 4 wire power cable. It is normally mounted in a sort of cage near the front of the computer and fastened in by two screws on each side. The cage also holds the CD/DVD drives and any floppy disk drive. The CD drives will look a bit like the above description, but you should recognise those by the fact that they poke out of the front of the computer so that you can put CDs/DVDs in the tray.

In a laptop computer the hard disk is smaller, typically nearly 3 inches wide by 4 inches long by half-inch thick. It has just one flat cable going into it, but this is typically built-into the structure of the laptop.

Typical hard drives from the top.

The Undersides:


Revised on 15 Aug 2006

Bill Williams

Edit MessageUploaded - 15 Aug 2006 16:19

Here is what a Hard Disk drive looks like inside. This particular one suffered a bad head crash which stripped the magnetic material completely off the area near the rim of the top platter.

NB. Do not open a hard drive which you wish to continue to use. They are sealed to keep out all dust down to a microscopic size.


Revised on 15 Aug 2006

Bill Williams

Edit MessageUploaded - 26 Mar 2007 19:03

If you buy one of these: [Link]
(thats for HD from a tower computer, I can't quickly find one for a notebook disk)
Then you could put your old Hard Disk drive in this new box, and use it with your new computer as an external disk.

You could then use it to make backup copies of your documents and emails.

Sort of in-house re-cycling :-)


Revised on 26 Mar 2007

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