After 8 months I restarted by old faithful PC with a new internet provider (Reliance). I found that I can access websites using their IP address, yet cannot access them using their name like www.yahoo.com. Interestingly nslookup worked giving me the proper IP address!
The stop-gap solution was to add to my hosts file, which isn't very comfortable. The DNS client service was running properly, so what gives?

I realized that I had set the DHCP client service to manual. On starting it, everything was back to normal. Can anyone explain why they have code which requires DHCP client service to be running to do DNS lookups? If nslookup can do it, why not DNS client service?

BTW: Reliance famed 114Kbps connection speed is actually 20Kbps, slower than my modem! So much for the hype.