"Rock" wrote:

> Sweatice wrote:
>
> > Anna, your post intrigued me. I searched this discussion group looking for
> > clues as to why a 40 GB Western Digital USB drive sometimes isn't getting a
> > drive letter but is getting connected (it can safe-removee; it is found to
> > be "working properly" by device manager).
> >
> > That problem remains unsolved, but your allusion to general unpredictability
> > of USB 2.0 in a Windows environment matches somewhat my limited experience:
> > USB drives sometimes showing a drive letter, sometimes not; a cable-powered
> > USB 2.0 hub used to connect two printers causing the printers to work
> > intermitently.
> >
> > I'd be interested to know if anyone can confirm the general compatibility
> > problems suspected by Anna or, better, shed some light on the causes of the
> > types of USB 2.0 problems that she mentions.
> >
> > Thanks!
>
> Hubs have been known to cause problems, particularly if they are not
> self powered, but even if they are.
>
> --
> Rock
> MS MVP Windows - Shell/User
>
>

Thanks, Rock, for the info that hubs can be a problem in their own right. Do
you know if the problem is with the USB 2.0 specification, or is it because
some hubs do not comply with the specification?

(I guess it could also be that the software--Windows XP in this
case--doesn't handle handle hubs correctly in all circumstances. Based on
what device manager shows under USB, hubs are a kind of object that XP
recognizes. and perhaps, then, also must manage.)

Sweatice