|If you have other computers on the LAN that are working, go to one of them and open a command prompt window and type the following command:|
Now do the same on the one that isn't working and compare.
The IP address should be different, but within the same subnet. The Subnet Mask should be identical.
If both of the above are true, you should have connectivity. You can test by using the ping command.
If you get proper replies back from the other computer, you're working.