vista,xp and xbox 360 lots of problems

I have bought a new laptop recently that came with Vista preinstalled on it and connected it to my home network that consists of 2 Windows XP machines and an Xbox 360 console as well as a linksys router. I have shared printer that is connected to the XP computers and most of this things are workin fine but not all. Even though the shared folders and printer can be seen in Vista on the XP machine but it will not connect to all shared folders, one of them says that dont have permission. It is also not able to connect to the printer with the same permission issue. The printer driver is already installed on Vista but if I am trying to connect directly by typing in the \\computername\printername then it will not connect. Also, the media sharing is already set up and vista sees it but the xbox is unable to see the vista machine? All other media services on the XP machines can be seen by Xbox. I had norton on my computer which I have disabled already and also turend off Windows firewall, but that didnt help me either. So, is there anyone who can help me to sort this issue? Thanks

For easier and faster discovery of computers on your home network, it is highly recommended that all computers on a home network be configured for the same workgroup name. If computers are in multiple workgroups, it can take additional time and effort to discover all of the computers on the network. To find out the existing workgroup name for a computer running Windows XP, do the following suggested on this link - http://technet.microsoft.com/en-us/l.../bb727037.aspx

I have followed each and every step on that microsoft website and have performed all the steps and setup, but still I am facing the same issue? Can you suggest some other method? Thanks for the reply.