Just to continue: it is also possible that you can see a server, then you click on it, and you see its shares (note that I still do not know why it sometimes succeeds, and sometimes not...), and then I want to attach a drive letter to a share which I see... It doesn't work, neither in the GUI, nor in the CLi with NET USE. I forgot the exact message, it was in Dutch, but anyway it was quite MS-like, something informative like "impossible to assign"