EXTERNAL FLOPPY DRIVE – Recognizes disc but can’t view files [duplicate]

A friend lent me an external floppy drive unit.
It works on his PC.

It is plug’n’play.
There is no driver available for download for this unit

I connect it to the USB port on my PC.
Norton Anti-Virus recognizes the 3.5” disc.
Norton scans many existent files for viruses.

However I cannot view any files on the disc.
The drive ( A: )(?) does not appear in Explorer.
I’m using Windows 7.

I tried a few floppy discs and got the same result.
I am now reluctant to buy my own such unit
in fear of getting the same result.

Any insight?