New Mac user here. These forums convinced me to buy a Mac and have been very helpful!

I just bought an Airport Extreme with one of the major reasons being I can connect an external HD to its' USB Port to share across the network.

I can't see the HD on any PC or Mac, nor can I see other PC's.

When I open the Airport utility and click on 'Disks', it does see the HD.

What am I doing wrong?

Thanks for any help!