In one recent case, it happened by mistake. At first, it was puzzling, then it was annoying, and then it was a little scary. A Bay Area man could not stop somebody else's e-mail from entering his computer.
So, he went to Michael Finney for help.
Ruben Rubio is a regular Best Buy customer, has a store account, and often receives e-mails from the company. There was never anything unusual until one day when he received a different customer's email.
"I don't know why this is coming to me, but my name is not Virginia Black," he said. "My name is Ruben Rubio."
His e-mail contained a receipt for a product he did not buy. The purchase was made in Michigan by a woman he did not know, by the name of Virginia Black. Right away, he figured the worst.
"Oh God, identity theft... Somebody took my card and is somebody is making purchases on my card in my name?" he recalled.
Rubio called Best Buy and they assured him no one used his account. The company promised to find out why he had received someone else's e-mail and put a stop to it. However, that was only the beginning.
"I received e-mail, after e-mail, after e-mail, after e-mail, with all her purchases, all her Geek Squad orders and times for pick-ups, everything she purchased: cameras, laptops, power supplies," he said.
Best Buy kept promising to fix the problem, but Black's e-mails kept coming. Soon, Rubio felt like he knew the woman, her buying habits, and her taste in electronics. More troubling, he had her Best Buy member ID number. In the wrong hands, he knew that could be misused.
"The implications that could happen if her information was to be leaked and they could point the finger towards me saying, 'Oh, you gave this person's information out,' when I didn't and my only concern was to get rid of it, not to see her information anymore," he told 7 On Your Side.
Months went by. Misplaced e-mails were still coming. Best Buy sent Rubio a $20 gift card. However, after that, Rubio received nine more Virginia Black e-mails.
"Who is Virginia Black? Every time I open my e-mail I'm seeing this person's information and it's weighing on me now after months and months and months. I said, 'well, what do I have to do to stop this?'" he asked.
That is when he called 7 On Your Side and we contacted Best Buy. The company said technicians were working on a software problem. It apologized for the delay and sent Rubio another gift card -- one for $50.
Finally, days after we got involved, the errant e-mails stopped. Best Buy would not say how the mistake occurred, nor whether Virginia Black was ever notified.
In a statement, they said, "While we cannot comment on the specifics of customer account issues, we can ensure that customer privacy is taken very seriously and no confidential information is contained in any e-mail communications."
Rubio is just relieved.
"I feel better," he said."I feel like someone put a blanket over me, that kind of comfort."
So, can you be held liable for receiving someone else's information? Our legal analyst Dean Johnson says "no," this was Best Buy's mistake. Rubio did everything right by notifying the store immediately.
A word of advice if this ever happens to you -- put that kind of notification in writing to protect yourself.