Hello,
I don't think, that WHS is the cause of the problem, it may be wrong or incomplete settings on your Vista client.
Which security suite you are using on it?
Did you check the settings on your laptop as described
here?
Can you ping the server by name from the laptop?
If not, please copy/paste the output of the command
ipconfig /all on both the server and the client.
Best greetings from Germany
Olaf