Now you see it, now you don't

There's no magic spell, but here are a few tricks for deleting - and retrieving - computer files

Chris Walsh, Rocky Mountain News

Monday, August 6, 2007

So, you deleted the document containing all your online passwords, cleared your Internet history after researching a medical condition and sent a few sensitive e-mails to the trash bin.

All that information is gone forever, right?

Not even close.

There's a good chance most of it is still on your hard drive, hidden from the casual user but accessible to someone armed with even a little tech-savviness.

That can be a good thing or a bad thing, depending on whether you deleted the data accidentally or on purpose.

If you want those files back, there are companies and software programs that can help - typically for a price.

But if you sold or gave away your computer, that information could end up in the wrong hands.

Despite the ubiquitousness of computers in today's wired world, many consumers still don't know much about how to delete - or recover - data. It's an increasingly serious issue as cases of identity theft rocket.

"Most people are really surprised to learn that when they drag a file into the recycle bin, they're not permanently deleting it," said Nathan Jones, vice president of sales for WhiteCanyon, which sells software for data destruction and recovery. "Unfortunately, that's not the way it works. Everything is still there on the system until your computer needs the space. Anybody who knows anything about computers can access it."

But there's good news. It doesn't take a rocket, er, computer scientist to clean up your hard drive.

Data remains until space runs out

The amount of data a computer contains is mind-boggling.

Anything you've viewed on your computer, be it an Adobe attachment or a YouTube clip, is potentially on your hard drive, even if you didn't specifically download and save it. The Internet pages you've viewed, the passwords you've typed in, the documents you've accessed all might still be on your hard drive.

"I think the average user has very little knowledge that lots of information on their systems is even stored there, let alone how to delete it," said Peter Watkins, chief executive officer of Boulder-based Webroot Software. "Many applications that you use create a large number of temporary files that will be snapshots of the information you've accessed. They are not deleted automatically. They are on your hard drive and take up space and present a serious security hole."

And it's a growing problem.

Millions of households in the U.S. are hit by identity theft each year, costing $6.4 billion annually, according to the U.S. Department of Justice. Many cases involve personal information that was gleaned from used computers.

Most users simply delete files by sending them to the trash or recycle bin. At that point the file is still on the hard drive and can be restored rather easily by opening the bin and using the "restore" command.

Even if you empty the bin, though, the files exist.

The hard drive "stores your e-mail information, the Web sites you've visited, your bank account information, your driver's license number if you've ever bought anything on your computer," said Steve Fuelberth, president and CEO of Denver-based Luminous Electronics Recycling. "Everything about you is going to be on your computer. And people stealing identities don't need that much information to do what they do."

Bulk of file info remains

Security experts compare deleting a file to tearing out a book's table of contents: The directory is gone, but the information contained in the book is still there.

When you simply delete a file, you're essentially telling the operating system it can overwrite the space that the file occupied. But it could take months or even years before that happens, depending on how much space you have and how often you use your computer.

"You may have a five-year-old computer that still has data on it from 4.9 years ago," said Brady Essman, founder of Arapahoe County-based DigitalMedix, which offers data recovery services.

That means you can recover a wealth of data that you've lost resulting from accidental deletion or things like weather events and computer viruses.

Data from drives that have been reformatted or don't work at all also can be recovered.

"It's good idea to never give up hope, even if (the hard drive) is in really tough shape," said Jim Reinert, vice president of data recovery and software products at data recovery firm Kroll Ontrack. "The majority of cases we work on are recoverable cases. Don't assume that the files are completely gone . . . just by the looks of the hard drive."

To truly erase data, the average computer user can download deletion software programs, physically destroy the hard drive or hire a professional to perform the tasks.

Denver-based Luminous Recycling, for instance, will grind your hard drive into bits for just a few bucks.

Software programs, which are available both for free and for purchase over the Internet, essentially go through and "wipe" certain files or the entire hard drive by overwriting the data.

"It takes about 15 minutes' worth of reading on the Internet to be fairly well-versed in how to destroy data," said Chris B. Hewatt, owner of Data Recovery Link and Computer Forensic Labs Inc., which are located in the Denver area. "If you really want to delete a file permanently, it's pretty easy."

How to permanently delete data

You have several options for completely erasing data from a computer's hard drive.

• You can "wipe," or overwrite, individual files and folders using erasing software, which is available for free or purchase over the Internet. Boulder-based WebRoot offers a product called Window Washer that overwrites data primarily associated with Internet use.

• You can wipe the entire hard drive with software such as White Canyon's WipeDrive, clearing it back to factory settings. This will eliminate everything, including programs such as Word and even the operating system. Users will then have to reinstall the operating system and other programs by using the disks that came with the computer.

• If you're super paranoid, you can physically destroy the hard drive by taking a sledgehammer to it yourself. A simpler way is to bring the drive or the computer to a company such as Luminous Electronics Recycling, which specializes in "shredding" hard drives and grinding them into bits. You can also buy an expensive degausser that puts a powerful magnetic field on the hard drive, erasing the information.

How to recover data

If you recently deleted files and emptied the recycle bin, there's a good chance you can recover the data. Same goes if your hard drive fails or if you lost information resulting from a virus, a natural disaster or a blackout - even if you reformatted the hard drive.

• Data recovery companies such as Arapahoe County-based Digital- Medix can revive everything from a precious photo of grandma to a video clip to a good portion of a hard drive. Prices vary, depending on the technical requirements of recovering the data and how much information you want, but it can costs hundreds or even thousands of dollars.

• You can download "undelete" software and other programs that help bring back files, images and documents. R-Tools Technology, for example, offers a host of software products that recover data from different programs, such as Outlook and Word. Prices range from about $20 to more than $100. Free programs and trial versions also are available. Some companies, such as Kroll Ontrack, offer multiple options, allowing consumers to use a software product or send in their hard drives for hands-on help recovering data.

Frequently asked questions

What information is stored on my computer?

More than you can imagine. Anything you've ever viewed, written or listened to on your computer could still be stored somewhere on the hard drive. This includes bank account information, online passwords, e-mails, Word documents and attachments you've opened - even if you didn't save the files to your computer.

What's stored on my computer when I surf the Web?

Anything you view on your browser - including pictures, graphics and other data on a Web site, even if you didn't click on them - is stored in temporary Internet files on your computer. Your computer also stores "cookies," which track the sites you've visited. You can easily delete that data yourself, but it'll still be on your hard drive until the computer overwrites the space.

What happens when I delete a file and empty the recycle or trash bin?

You essentially remove the "address" that tells the computer where that file is stored and let the operating system know the space that file occupies is available if needed. The file remains on your hard drive until the computer decides to use that space for new data, which can take years depending on how much memory you have and how often you use the computer. "Wiping" the drive essentially overwrites the files.

What should I do before getting rid of my computer?

If you're donating or selling it, experts say you should either completely wipe the hard drive using software available over the Internet or bring it to a company that'll do it for you. Most organizations that take computers as donations have the software to reload the operating system and other programs if you wipe the drive.

If you're just giving it to a family member or close friend, you should use software that deletes certain files and folders but not necessarily the whole hard drive.

If you plan to get rid of it, you should wipe the hard drive, destroy it yourself or bring it to a company that will physically shred it.

Should I be aware of anything when erasing files?

Some software programs will completely erase everything on your hard drive, so be careful which one you choose. It would be a disaster if you just want to permanently erase a few files but end up wiping out everything.

• whitecanyon.com

• digitalmedix.com

• webroot.com

• luminousrecycling.com

• r-tt.com

• ontrackdatarecovery.com

walshc@RockyMountainNews.com or 303-954-2744