I would suspect that although both cows show up in Hypervue, Windows may not be seeing the Network.

To overcome this I started a "Home Group", which is new to Windows 7, and then got both computors to join the "Home Group". When you start a Home Group, Windows will assign a Password, which you'll need to record.

Adriaan Barel (a.k.a. Vege Mite)
"Morality, like art, means drawing a line someplace." -- Oscar Wilde