bank's computer. The machine was then sold without the files or drive
being wiped clean. The data was then discovered, and the story ended
up all over the news about how this particular bank and possibly
others like it were not taking precautions to erase data on old
computers, which were later sold or donated.
Forgetting to delete pertinent information from any hard drive is
worrisome. Copy machines also pose risks. As CBS reported in April,
since 2002, most copiers are installed with hard drives that save
images of all copied documents. When these machines are then sold or
discarded, the stored information, which can include private
information such as medical records, frequently remain intact.
What does 'delete' mean?
Many users are still convinced that when they delete a document or
file on their computer, it vanishes into thin air -- but that's hardly
the case.
As "Sam," a security engineer who wishes to remain anonymous because
of the nature of his job, explains: "When a user 'deletes' a file,
it's not really gone. Deleted files are sent to the Trash folder. At
this point, files can still be recovered." However, even if the Trash
folder is emptied, it doesn't mean the file has disappeared
completely. "But the longer a deleted file is left on a drive, the
greater the chance the file cannot be recovered," Sam says.
Everyday PC maintenance
There are a number of programs out there that help ensure that your
deleted files are really deleted. In addition to guarding your privacy
by removing traces of your Internet browsing history and files and
programs you have used, Computer Checkup Premium also cleans
registries, removes clutter by clearing out temporary files, and helps
solve the problem of a fragmented hard drive by rearranging data so it
can be accessed more quickly.
If you have accidentally deleted files, Computer Checkup Premium also
offers an '"undelete" function.
Formatting and disk wipe
Then there are times when you really do need to permanently delete
everything. If you are in the process of donating or selling your
computer, or if you have sensitive information stored on it which you
wish to be deleted permanently (such as medical information, bank or
legal documents, or Social Security numbers), tech experts recommend
reformatting your hard drive or performing a disk wipe. According to
The Tech FAQ, "Formatting the hard drive or any of its partitions will
completely erase all data that is present."
A thorough "disk wipe" will essentially overwrite your hard drive to
the point where recovery is impossible. As "Sam" explains, "When the
U.S. Government wants to delete information from an entire hard drive,
it employs the Department of Defense disk wipe, which means the entire
drive has its data overwritten with a random pattern of zeros and ones
(binary data) three times. At this point, any data on the hard drive
is considered unrecoverable. In some instances, the platters are
removed from the hard drive and dipped in caustic acid -- referred to
as 'erase by physical destruction.'"
Users can (and should) erase the hard drives of their old computers so
their data cannot be found by anyone else (think Paul McCartney). One
program "Sam" and other tech experts recommend is Darik's Boot and
Nuke, which will delete the contents of a hard drive with certainty.
Consequences of not deleting files
Sensitive information carelessly stored on computers can lead to
identity theft, and also harks the growing need for computer
forensics.
In 2007, for example, a forensics expert found that the new publisher
of the Minneapolis Star Tribune had transferred sensitive information
over from his St. Paul Pioneer Press computer, where he previously
worked. In another case, the insurer Health Net was recently sued as a
result of a missing computer hard drive that stored the medical
records of several thousand customers.
Deleting files from your computer is similar to shredding documents:
Store what you need, and digitally "shred" those you don't.
