|If you are physically connected but you still cannot access the Internet it is a good idea to proceed to check your ip configuration to make sure that a Default Gateway is assigned.|
The Default Gateway is normally a router which is used to connect your internal local area network to the actual Internet. Without a Default Gateway assigned you will not be able to connect to the Internet.
While there are various ways to check your IP configuration one of the best commands that PC technicians use is the IPCONFIG command.
Open a command prompt window by clicking on the Start Button, then Run, and finally type the command CMD, and hit enter.
In Windows Vista feel free to type CMD in the Search box.
Once you are in a command prompt window type the command IPCONFIG and hit enter.
if you do but still cannot access the Internet proceed to release and renew your IP configuration.