I have two computers connected to a switch witch than is connected to my router. The problem is that one of the computers cant get into the nettwork. It has worked, but yesterday it just stopped.. Whene i check my automatic ip on the comp thats working it has ip 10.0.0.5 and subnetmask: 255.255.255.0, but the one thats malfuncioning has ip: 169.254.122.85 and subnetmask 255.2555.0.0 and i cant renew the ip. This results in the comp not geting onto the internett or the nettwork.. whene i set it too the right ip it still will not work... please help..

Your machine ain't being allocated an ip and has ended up with APIPA With APIPA, DHCP clients can automatically self-configure an IP address and subnet mask when a DHCP server isn't available. When a DHCP client boots up, it first looks for a DHCP server in order to obtain an IP address and subnet mask. If the client is unable to find the information, it uses APIPA to automatically configure itself with an IP address from a range that has been reserved especially for Microsoft. The IP address range is 169.254.0.1 through 169.254.255.254. The client also configures itself with a default class B subnet mask of 255.255.0.0. A client uses the self-configured IP address until a DHCP server becomes available. The APIPA service also checks regularly for the presence of a DHCP server (every five minutes, according to Microsoft). If it detects a DHCP server on the network, APIPA stops, and the DHCP server replaces the APIPA networking addresses with dynamically assigned addresses. First thing to do is check connections and make sure this isn't a physical problem.

Well.. i have two nettworkcards, i have tried both, taken away one of them, changed the port on the switch and changed the cable..

Perhaps clarity of testing order should be considered. So you have a working and nonworking cards. Did you simply swap cables at the nics to see if the other [working card] failed? This would test cable and port. Solution would be to replace the faulty nic. Have you "reserved" ip addresses in your router? In other words have you associated a ip address with the nics mac address so the same pc gets the same ip address? If you did and swapped nics it would not get a ip assignment if all dhcp addresses were reserved. If you put the working nic in the nonworking computer do you get a ip address? Problem is nic/cable/switch port/dhcp configuration so you have to isolate which is the problem.