Trouble sharing music and movies ono pc

Ok I have got the hub to play movies i have copied over to the hd just fine, I love that feature.

I have about 1400 songs in itunes on my pc which is win xp

I just can’t seem to figure out how to get the hub to see folders tha ti have shared on my pc. They don’t show up on the hub

I also have zero luck finding step by step instructions on how to set up a network share or have the hub automatically update its list form my hsared music folder which is onmy pc

Do i NEED to downlaod and install twonky or whatever on my pc? i thought it was built in to the hub

heres a link to help