Ok, my Xbox 360 got sent away to Microsoft couple of weeks ago due to the RROD. Received a replacement console today. Connected it all back up and when it tried to connect to Live it says it needs to download an update (I was expecting this). So I agree then it looks like its about to start the download then comes up with an error message saying its unable to download the update and to check network settings etc.
My Xbox was previously connected to Xbox live before it got the RROD and I haven't changed any of the settings on the router or anything.
Anyone got any ideas how to fix this???