On Sunday 26 February 2017 22.17:36 Curt Howland wrote:
> This happened to me as well, on drives where I had written a DVD .iso
> image. The DVD image would still mount, even though there was nothing
> there, after I repartitioned and reformatted.
>
> I used "wipefs" on the device to clean out the old file system tags.
> All of them. Then repartition, reformat, and only the active partition
> showed up.
>
> Maybe some experimentation would allow for a "wipefs" command that
> only wiped the "macUSBdrive" tags, but I didn't spend that much time
> on it.
>
> Curt-

Thanks, that's a trail I can follow. I have  afew older sticks I could use for 
testing- I'll report if I find something.

Thierry