I follow your advice, and I got this interesting results:
In this direction appears the list of letters that one has activated for the diferent units, as you saw in the Windows Explorer picture, the unit with problem is the J:. So, as you can observe there is a KEY called DefaultLabel with a value (predetermined) -in the picture (predeterminado) because is in spanish- with Data (in the picture Datos) that has been making my mind into pieces. In a first step I deleted the DefaultLabel entry, but as soon as I rebooted or press F5, the KEY reappears again :Z . And that really pissed me off :a , but I cooled down (again!), and make a search with the word Naota and found the next entries:
In this entry there is only the J unit, with the annoying "Naota"
It looks exactly as in the first case, just that in this direction.
I deleted every entry, and at last the problem was solve . It has been interesting, it's the first time I see somehitng like this. I hope this could help someone, sometime.
Thank you, everyone who post here.
PS: Sorry i don't know how to insert the images corretly in the places I want.