Sorry to jump in on this thread but I have had exactly the same issues as Kathi.
I have tried every combination of the Network and Sharing Center's Sharing and Discovery settings, but currently they are:
Network Discovery - On
File Sharing - On
Public Folder Sharing - On
Printer Sharing - On (printer sharing doesn't work either)
The Vista PC has Windows firewall and the XP PCs have Zone Alarm. I have tried uninstalling this to no avail.
I can ping the VHP PC from the XP PCs.
Any help gratefully received. Thanks
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