Is there a limit to devices windows explorer can show ?

Have a tricky issue, I've looked through the forums and found a similar
problem but not the same one, I got a new western digital internal sata
500gb hdd, It doesn't show up in windows explorer, But i went to admin
tools/somputer management/storage and formatted a partition on the new
hdd and i gave it drive letter T: but it's still not in explorer, Also I
have a usb stick that wont show up, It makes the noise like a new
connection, but nothing, I go into computer management and it's there,
And works fine in XP, I have another usb stick that works just fine all
the time is there a setting somewhere i need to change, any
suggestions??


gigabyte GA-MA69MV-S2
amd athlon 64x2 4200+
2 gb ram
evga geforce 7600 gs
windows vista ultimate 64


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Fisti

Thanks for the help everyone, but I got it, I went into computer
management/storage and right clicked on the drive and went to explore
and that brought it up, so I dragged it from the left to the right side
on my computer and now it shows and says (9)hard drives, also changed
the drive letters on my other stuff like my card readers and virtual cd
moved them to the end, Not sure exactly what it was but now my usb
sticks are working again hmmm....????


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Fisti