Try this link:
http://www.microsoft.com/technet/network/evaluate/vista_fp.mspx
It solved some of my problems. I can see the vista system from the xp system but cannot access files. Check out the "Hardware>Networking & Wireless" forum, the post "xp to vista network" for some more information. If you figure it out let me know. I am still struggling.
This may be a long post and I'll try to explain it as best I can, please bear with me.
I have an office network that consists of a Server Computer running Windows XP. At one time we had three client computers running Windows XP connected to the Server Computer and a Satellite internet connection using a Linksys 10/100 5 Port Network Hub (Model # NH1005) and a D-Link Ethernet Broadband Router (Model # DI-604). Everything worked pretty good.
We've replaced one of the client computers with a new Compaq with Windows Vista. It's able to access the internet fine; however I can't access the files on the server computer. The Network and Sharing Center only shows a connection from:
Vista Client Computer -----> Network ------> Internet.
It doesn't show any of the other computers on the network or the server computer. I've went through the quick fix issues on the Windows site. I tried disabling the firewall, made sure the Network Discovery was on, and made sure the Public Folder Sharing was on.
I pinged the Server Computer and one of the XP Client Computers from the Vista Client Computer and all the packets were sent 100%. But when I pinged the Vista Client Computer from the XP Server Computer the Request Timed Out. When I pinged the Vista Client Computer from one of the Windows XP Client Computers it timed out again.
So I'm at a loss for what I should do next. I only have a limited knowledge of networking as I didn't set up this network in the first place. So any tips, pointers, or advice would be greatly appreciated. Thanks in advance.

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