jss2020 said:
Thanks for your response.
I am supposed to get the IP address from Comcast. It is a cable mode. There is no router. The connection is wired. My XP Pro desktop connects fine to the net.
The laptop has Windows 8. When I plug in the Ethernet port it tried to identify network and then said "Unidentified network".
While trouble shooting I got these messages:
'Ethernet' doesn't have a valid IP configuration
Investigate router or broadband modem issue
If I try to create a new connection, I get Broadband PPPoE which asks for username and password which Comcast doesn't provide.
I plugged the same Ethernet cable in laptop that was in desktop.
Rebooting didn't bring up the network.
IPconfig didn't release/renew did not work either.
If the desktop can access the DHCP server why can't the laptop? That's what I am wondering.
compare IPconfig /all from you desktop
to the one obtained from your laptop
-If you are getting your ipaddress from your cable company, they are not responding to the DHCP client request in a timely manor and your laptop reverts to a cached IP address that is not valid on your current network.
-Some cable cable companies want to charge you for a second address and restrict the number of devices. If this is the case you can work around it with two methods, 1) set up your own router
2) power down you cable modem and physically disconnect the broadband cable that goes into the cable modem (big round black cable, not your ethernet cable)
3)leave your cable modem disconnected for a few mins, you want the cable company hardware to actually detect the loss of your cable modem device. When you plug the cable back in and turn it on the cable company servers will have to respond to the clients request for a IP address and you will feed it into the machine that you connect to your ethernet port.
4) now after your laptop is working, shut it down so that the new address will be saved as the default address.
At this point you should have two machines configured to run default address that will work on you network even if your cable company will not issue a second address. Problem is you will have to do this each time they change your address and you will can only have one machine up at a time.
if you bring both machines up you will get a duplicate address error and one machine should refuse to send data.
lots of times it is just easier to spend the $29 and get your own router and not worry about these problems.