Here are some simple words of wisdom from one who has for decades made use of all sorts of portable magnetic media. Don’t trust it!
This simple message, a public service of sorts, was brought to mind when my wife recently came to me with a small portable USB hard drive in her hands. She had just plugged it into her PC which had responded by asking if she wanted the drive to be formatted? The implication being that it was not already formatted!
Of course, the unhappy little drive in question is a 320 GB 2.5″ USB drive that she had been using to shuttle all manner of valuable bytes from here-to-there.