Operating systems are typically very messy, leaving lots of little trails and images for people to follow. This is in no way troublesome when you are using your computer, and you are the only person who has access to it. On the other hand there are always situations where a computer might be used by another person, your hard drive might need to be replaced, and data could fall into wrong hands. To protect against this many companies and individuals do a simple restore or wipe of their hard drive, believing that this completely takes care of the problem. In a word – it doesn’t.
When you wipe a hard drive or install windows as a reinstall, all the software does is erase the indexes and re-files the data in a different part of the hard drive. This information can easily be access and transferred by anyone who knows what they are doing. A complete format does pretty much the same thing and so it too has only limited usage when attempting to completely remove data off a hard drive. Unfortunately the way programs are written today they make a lot of entries which can be used to trace back to data and bring that data back to the surface, recover it and use it for whatever purposes the user had in mind.
There are several ways an experienced technician can deal with this and there are two ways, you as the user can protect your data. Let us start with the latter option since that is what should be used on a regular basis by all users to ensure the sanctity of their data.
Using a windows login goes a long way towards protecting your data by assigning a select and password protected area to store your files in. This allows for multiple users to get on the same computer system without having to intrude onto each other’s files, save them appropriately, and when necessary delete them. Bearing in mind of course that this does not still take them off the computer and in the hands of a good technician the passwords and other protections are merely superfluous.
Windows is a good place to start, and it is always highly recommended that profiles be set up with the appropriate security settings and access. For companies this can be a key component to security because it allows for limiting the access by login to servers and other classified company information, thereby reducing the risk of data being on an inappropriate hard drive in the first place. A company or individual that provides technical assistance to companies or individuals can set up windows log on’s to be very specific and provide detailed instructions on storage, what can and cannot be accessed, and functionality based on the specific login.
A second option is to use encryption software for all saves. This allows the data to be effectively scrambled and thereby does not allow anyone to see the data in its truest form, the way you entered and saved it, without the passwords and the un-encryption capabilities. This is a slightly more high tech solution than windows and requires that you have third party software installed. It also requires passwords, and more importantly remembering passwords to get the data back when you yourself need it. Encrypting data is a great idea, however, it needs to be stressed that it is not a catch all simple solution. The data, encrypted or not, remains on the hard drive and can be recovered should someone have the time and the desire to do so. There are other solutions that are available, most are expensive and not very user friendly. If, however, you find yourself in a position where erasing the data on a hard drive is very important, it is best to speak with a qualified technician or programmer who can do a much better job and actually erase a lot of the data. While they are not magicians, and some data will always be accessible, a well trained technician can make it a lot harder to recover data if at all.
One of the ways all data can be removed from a hard drive is to first run a normal format, or reinstall. After the formatting has completed, then the hard drive needs to be cleaned of cookies and other saved pieces of data. Finally the “empty” places on the hard disk drive should also be wiped clean, because of the tendency of Windows and other operating software to save old and deleted files in the empty locations. As mentioned before when doing a reinstall or wipe of the data areas Windows tends to delete the index and keep the actual files, which I then stashes in the empty area of the hard drive. Deleting these areas can be a time consuming and effort filled endeavor best left in the hands of a seasoned technician.
All of these things can be done with the help of a special purging or wiping software, and will usually take several hours to complete. Also known as a “bare-metal” purge, it will be necessary to reinstall all drivers and operating systems before the hard drive can be operational again, making it virtually impossible to then transfer any or all data should the hard dive move to a different computer or be used by a different user. It is important to remember, however, that a completely irrecoverable purge of a hard drive simply does not exist, outside of the costly method of setting fire to the device.