Here's Microsoft's take
What you have to do is check the TCP/IP settings on the computers which are in conflict.
One or both of them might have static IP addresses as opposed to addresses served from your router (DHCP).
I've been perusing around a Windows 7 machine I have here and I not found out how to do that. On a Mac I could tell you.
I think in Local Area Connections, there might be an option...but not sure.