The DHCP solution works if you are not getting a valid IP address.
If you are not getting and IP address or you get an IP address starting with 169 then you are not getting a valid DHCP address. Example: 220.127.116.11
If you are getting an IP address similar to other devices on your network, then you likely have a different issue.
I had a very similar issue as the OP. My internal network connection was fine and Network and Sharing Center showed a network and internet connection with no Red X or Yellow Triagnles. However, I could not get out to the internet or ping internet sites like google.com (or its equivalent IP address). Mind you, that not all websites are pingable.
I had checked Proxy settings in IE, disabled IPv6, checked netbios Default (use Netbio setting from DHCP server...), uninstalled and reinstalled Client for Microsoft Windows Networks, and a few other things. DNS was fine as well.
What fixed my issue was resetting the Winsock TCPIP configuration.
I used the following command after opening up a command prompt as administrator.
netsh winsock reset
I was immediately able to ping google.com, go to various websites, etc. but a reboot should be done right after.
Hope this helps someone.