Vista-XP Networking Problem

At my office we have our main computer which is XP (has the printer hooked to it) and a new computer running Vista. We have a network through a lynksis router. The XP is hooked by a cord and the Vista is hook to it wirelessly. The main computer isn’t having any problems but the Vista is. Through the network I can get the Vista on the internet but it wont recognize that the XP is there to share files with and it wont let me use the printer (which is set to share).

I have went in to each computer and made sure that the network is named the same since the default names aren’t.