Looks like you have a network problem what is your network hardware?
and what is the output of ifconfig?
I tend to agree - I think my initial eth0 problem has come back to bite me.
The original problem was that the dns info was not getting set by my router straight away, it took some time, not sure what actually got it going.
ifconfig does not return anything at all; prior to the install eth0 and lo were listed. Not a good sign
The NIC is onboard the P55-UD3R MB using RTL8111D chip.
I checked the content of /etc/network/interfaces
iface lo inet loopback
iface eth0 inet static
iface eth0:1 inet static
I think I might try dhcp for eth0 and see if that makes a difference.
Failing that, I will manually enter the subnet and gateway.
Let me know if there is anything else I need to check.