How Best Buy’s computer-wiping error turned me into an amateur blackhat

Are you returning a computer to the shop for a refund, part exchange or similar, this is worth reading and a good lesson about what could happen. In short, ALWAYS at the very least return it to factory settings to remove your data.
 

Or, how to compromise Windows 8.1 through Web search and open source software.

by John Ferguson (US) - Jun 13, 2015
 
We put a lot of trust in big companies, so when they let us down it can have serious consequences.
I recently went shopping for a new computer. I wanted a low-end laptop for light work, and the HP Stream seemed like a good deal. That deal was made even sweeter when Best Buy offered to sell me a returned one for almost 20 percent off. The salesman assured me that it was in like-new condition and that they would honor all warranties. Sold.
 
I always get a little thrill opening a new gadget. The computer looked like it had never been touched and all the paperwork was still in sealed bags. There was even a slip of paper in the box with the ID of the tech who cleaned and certified the unit.
 
So it surprised me when I booted up and saw someone else’s name and Hotmail address at the login prompt. So much for like-new!
As I stared at the full name and e-mail address of the previous owner—let’s call him David—I wondered. Could I get into this computer another way? It was mine after all. And how much more could I learn about him? How bad of a mistake had the store made?
 
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