Log on to the router (you may need to do this from another computer), and look for a list of connected or attached devices. The MAC address of one of them should match the MAC address of the computer. You can fint the MAC address by running command.com and type 'ipconfig /all'. The MAC address will be referred to as the "Physical Address". If there are coinciding MAC addresses, the physical connection is properly connected.
While you are in the IP Configuration, check to make sure there are propper addresses for the following: IP address, Subnet Mask, Gateway, DHCP server, and DNS servers. If there are any apparent issues with any of those, go to Network Connections, then go to the properties of your Local Area Connection. Select "Internet Protocol (TCP/IP)" and click Properties, then make sure that everything is set to be automatic.
Finally, make sure protocols are registered so you can browse.
Use this batch file that I made for
another similar problem. I think I may have missed a few, but that should be enough for Mozilla or any other non-IE browser to work fully.
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