Your Privacy Exposed!
By John Anderson

Deleting Your Files

When Microsoft introduced the Recycle Bin in Windows 95, it immediately became a failsafe for many users. If you delete a file and realize that you actually need it, you can recover it easily by opening the Recycle Bin, finding the file you want to recover and restoring it to its previous location.

A common misconception is that the data is actually removed from the hard drive (erased) when you delete a file. Any time that a file is deleted on a hard drive, it is not erased. Instead, the tiny bit of information that points to the location of the file on the hard drive is erased. This pointer, along with other pointers for every folder and file on the hard drive, is saved in a section near the beginning of the hard drive and is used by the operating system to compile the directory tree structure. By erasing the pointer file, the actual file becomes invisible to the operating system. Eventually, the hard drive will write new data over the area where the old file is located.

Data Recovery

What happens if your hard drive crashes or you accidentally delete a needed file. There are several utilities that you can find on the Internet that allow you to recover “deleted” files. What these utilities do is search for data on the hard drive that does not have corresponding pointer information and present you with a list of these files. Your chances of fully recovering a file diminish the longer you wait after you deleted the file since the probability that the file has been overwritten increases. Sometimes you can recover portions of a file that has not been completely overwritten. You can do this with programs such as Undelete 3.0 from Executive Software (www.execsoft.com).
For the really tough jobs data recovery firms can get your data back from such disasters as computer viruses and lightning strikes.

The Wrong Hands

But what if you deleted the file for a reason and you really want it gone? What happens to this data when it’s time to get rid of your PC? The old PC and all of the data on it can end up in other people’s possession whether your PC is being donated, recycled or transferred to another user. You could be sharing information of a very personal nature, such as:

• Financial information/investment records
• E-mail messages
• Classified business documents
• Legal documents
• Internet history
• Personal documents
• Client information
• Trade secrets
• Credit card numbers
• Social Security numbers
• Address books

Simply deleting the files from the hard drive won’t protect you from some of the more common file recovery programs on the market and certainly not from some of the more sophisticated tools used by professional recovery experts. This is especially important with the new HIPAA rules and regulations regarding health care information.

Using a widely accepted analysis program called EnCase, professional forensic examiners can find sensitive data that has not been permanently deleted from a computer’s hard drive.

Once used only by law enforcement, computer forensic examinations are now widely used by attorneys for employment and business litigation and have proven instrumental in many criminal cases, including San Diego’s Westerfield Murder Trial, Chandra Levy’s disappearance and the terrorist attacks in 2001.

Many large corporations and government agencies are equipped to handle the disposal of hard drives, but most small businesses and home computer users lack formal disposal guidelines, expertise and software. Firms entrusted with private data must implement measures to safeguard their client’s information or be faced with the danger of having this personal information fall into the wrong hands.

Shred Your Data

Normally the issue of security is focused on keeping intruders from gaining access to your information remotely. But another far more concerning risk is the accessing of your files directly from a discarded hard drive. With increased personal identity theft permanently deleting data should be a priority. When recycling used computers, hard drives must be wiped clean. Merely reformatting a hard drive does not permanently delete information.

The only way to properly “shred” data is to use programs like Symantec’s WipeInfo (www.symantec.com) or Access Data’s Secure Clean (www.AccessData.com), which permanently overwrite data, making it virtually unrecoverable. Of course, to ensure that sensitive information is not retrieved the hard drive may need to be physically destroyed.

According to a new study companies and individuals frequently sell or give away old computer disk drives with sensitive information still on them. The study analyzed 158 disk drives purchased through EBay’s online auction site at computer stores, salvage companies and swap meets. The study found that 117 (74 percent) of the drives contained old data that could be recovered and read. Twenty-eight of the drives (17 percent) contained fully-installed, functional operating systems with user data that required no particular effort to recover. Another 57 (36 percent) had been freshly formatted but still contained old data that could be recovered, according to the report. Only 12 disk drives (9 percent) had been properly cleaned (or “sanitized”) before being purchased by the students, while 29 of the 158 drives purchased did not work.

What to Do with Old PCs

The useful life of a computer is three to five years and shrinking. By 2005, more than 63 million PCs will be retired, according to a recent study by the National Safety Council. The EPA has warned that end-of-life electronics pose serious issues regarding proper disposal and potential environmental consequences. Smart PC disposal options:

• Donate your PC to a good cause.
• Recycle your PC and protect the environment. Many of the parts could be refurbished and reused with little effort. When we throw away old electronic equipment, we’re throwing away resources and sometimes generating hazardous pollution.

If you plan to either donate your PC or recycle it and are concerned about your data do more than just delete your files or reformat your drive. Employ data deletion software or have the hard drive removed and destroyed. You’ll sleep better knowing where your data is.

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Publications : Bar Bulletin: August, 2003