Linksys router troubles

Hello,

I was wondering if there was a way to permanently fix this problem. I recently got a linksys wireless router last week. I have three computers hooked up to the router, one is a desktop which is connected with wires and two other laptops which are connected wirelessly (a MAC and a Vista). I took the Vista laptop to another state and when I came back home, the internet connection would not work. It acknowledges the network name but cannot connect to the internet. I've called linksys twice and they have helped me solve the problem but I want to permanently resolve this issue.
Linksys says its an IP address conflict and one linksys person said that it is possible that the Vista laptop has some issues since my internet connection still works for the desktop and MAC laptop. Then again I have not tried taking my MAC laptop to a different location other than my home. So I do not know if it could possibly be a MAC issue.
I noticed in another linksys forum question that someone suggested to turn off the IPv6. Should I try this for my situation as well? Any help would be beneficial.