Transcript for How to Sell Phone Without Selling Out Privacy
We are back with "Gma" investigators this morning. We look at the risk of selling your old phone. So many of us do that before upgrading. Could be packed with your private information even if you think you wiped it clean. Gio Benitez has the story on how to protect yourself. Reporter: More and more people are selling their old phones online. It's quick cash to put towards that upgrade. But technology experts now warning consumers to be careful. Most people have no idea how much information is on the phone. Reporter: To better protect you, a group of analysts set out to do an experiment. We went on to Ebay and bought five or six auctions worth of old cell phones. Reporter: To see how many people don't properly wipe personal data before reselling. Out of nearly 100 phones -- 31 of them had what I consider to be some pretty disturbing personal information. Reporter: And there's real information that a real crook can do something with. Social security Numbers, bank account Numbers, pass words. Reporter: Even simple information, doctors appointments in the calendar can be dangerous. They call up, from the doctors office. Need your credit card number. Reporter: They tracked down Lacey, an original owner of one of the phones they bought online. I haven't slept for a week thinking if my phone had been in the wrong hands. She sold the phone to a company that promised to wipe the personal data. At the time, $125 and I bought a phone. It was a good deal. Reporter: But the phone -- 13,000 text messages, 120 e-mail messages. 120 bucks is not worth your life. Reporter: A common mistake, putting it back to factory settings. "Gma" investigates wanted to see what that would do, is a we reset the old iPhone 3g. And manually deleting any old text messages and e-mails on the phone. Now see if we can bring it back. Reporter: And with a little digging, we find all of her original information still on the phone. 2,838 photos extracted. While they use celebrite, a state of the art program to use datas, they can get that for free. How do you protect yourself? Each phone is difference. Typically, go into the settings and erase all data. Reporter: For our producer's iPhone, it's a few easy steps in the settings menu. Rerace all content. Reporter: And thshds wipe it clean. Yes. Even with the equipment, we won't be able to get anything back. Reporter: Gio Benitez, ABC news, Boston.
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