When selling your phone or laptop is not worth it

Thinking of selling or giving away your smartphone or laptop computer? If you have a BlackBerry or an iPhone, go right ahead. But if you have an Android phone or a computer running Windows XP, you may want to hold off.

It turns out that it's almost impossible to get rid of personal information from some devices, even if you follow the manufacturer's directions for wiping the device clean.

Robert Siciliano, identity theft expert for the technology security firm McAfee, found this out in an experiment he conducted over the fall and winter. He bought 30 electronic devices from Craigslist — mostly smartphones and laptops — to see how effective people were at removing personal information from their gadgets before selling them.

Siciliano was shocked to discover that some people didn't take any security precautions at all before selling a computer.

"One guy asked me to log him out of Gmail if he was still logged in," Siciliano said. "I had no idea how naive some people can be."

In the end, Siciliano was able to glean personal data from 15 of the devices through his own hacking efforts and the help of a forensic expert. That information included bank account information, Social Security numbers, child support documents, credit card account log-ins and a host of other personal data.

And the worst part? Most of those phones and computers had already been "wiped" by their previous owners — meaning all personal files had been deleted and the user had restored the device's factory settings as per the manufacturer's instructions.

So, what's the difference between the devices that still reveal personal information after being wiped and those that don't?

Siciliano said it came down to the type of device and the operating system. BlackBerrys were totally impenetrable.

"RIM has fantastic software," he said. "They did a really good job of destroying data when you reset the factory settings."

Devices running iOS, such as the iPad and iPhone, and computers running Windows 7 can also be wiped clean of personal data, as long as a person follows the manufacturer's directions.

As for smartphones running the Android system and computers running Windows XP, Siciliano said he recommends people don't sell them at all. "Put it in the back of a closet, or put it in a vise and drill holes in the hard drive, or if you live in Texas take it out into a field and shoot it," he said. "You don't want to sell your identity for 50 bucks."

— Los Angeles Times