Network Problem . Urgent reply please...?

I have small work station in my office. No servers . Internet is connected in the modem and then to hub . Using 10mbps hubs. My problem is In my work station one Computer is not connected with the network . The other computers are already connected with the network. I have check the IP, DNS and all the network services . Even i change the cable also . This computer are connected with the network on 5 hrs before. What can i do now to connect that computer with the other computer networks ?? My NIC card also working properly. I have ping 127.0.0.1 and its works fine . Need the answer very urgent .

Network Problem . Urgent reply please...?
Coleman has a good answer. One other thing I might try if that doesn't work is to plug the "bad" computer into the network by unplugging the cable from a "good" computer. Log off and then Log back on. You say IP address is fine. I presume it starts with 192.168.x.x Make sure it doesn't duplicate another on the network. Also double check the subnet mask against the other computers. 255.255.255.0 is not going to work if the others say 255.255.0.0


Can you connect the "bad" computer directly to another computer not using the hub? maybe one of the ports on the hub is bad.


try booting into safe mode with networking. (restart the computer and hit f8 until you get the safe mode choices) see if you are able to access the network then.


These are all just suggestions and I don't mean to sound condisending but I don't know your computer expertise. When I troubleshoot peoples problems on the phone, these are things I would do first.


GL
Reply:What did you do to change the settings from 5 hours ago when you were online? Did you install software? Did you change cables? Go back to where you were before. You did not mention what operating system which makes it difficult to diagnose. XP can "repair" the connection, by opening Network Connections in Control Panel, and by pointing to the connection, right click, and select "repair".


If you do not have XP, in most other Windows systems just try open a command prompt then type "ipconfig release" followed by enter


then type "ipconfig renew" followed by enter.


To get to the command prompt type "CMD" in the run box.


If that does not work, then try uninstalling the Nic card and reinstalling. Finally, power cycle the computers, the hub, and the cable modem. When you turn all of those off, leave them powered off for one minute before plugging them back in again.
Reply:On a computer that is connected to the network, right click on My Computer, click Properties, click Computer Name, and write down what the workgroup is. Now, on a computer that is not connected to the network, right click on My Computer, click Properties, click Computer Name, and click change. Replace the name next to Workgroup with the name of the other computer's workgroup, which you wrote down.