This question already has an answer here:
- How do I add a DNS server via resolv.conf? 18 answers
I have seen some questions similar to mine but not the same. I have just gone through the process of installing 12.04 dual boot with WIndows 8. Before I resolved all my boot issues and ran ubuntu I could connect to the internet no problem. Now I can connect to my router and ping is OK, but no applications can reach the internet. pinging google fails.
On a similar user question someone suggested pinging 220.127.116.11 That does work.
I think this went bad for me when a large number of updates were installed.