can't renew ip address to get online

[mheidi]

I'm not able to access the internet-have Windows XP. It appears that the problem is that my computer won't renew the ip address. I've tried ipconfig/release - which worked fine, but when I tried ipconfig/renew - nothing happens.
I've done flushdns, reset winsock, checked under administrative tools and services to make sure dns client was enabled-automatic, I've restarted about 18 times, and I'm still getting the 'limited or no connectivity" message, although it can tell me the speed (100 mbps). I'm using a laptop with a Comcast modem with ethernet cable, and I know the connection is good because I've been hooking the same cable up to another laptop(Windows Vista w/IPV6) and it works fine. Does anyone have any ideas on what else I can try? I'm kind of a beginner, and this is probably a stupid question, but could it be my NIC card? or the driver?
Thanks,
Heidi H.

[starfireone]

Most of the time when I have ran into this issue it has been only a few things. One: my firewall was blocking the ipconfig renew from being sent through the cable modem/router. Check your firewall to make sure it is not blocking that port. or shut down your firewall for temp time and try to renew. Do not leave your firewall shutdown for very long. Two: my cable modem/router needed to be reset. A reset fix the problem Three: my cable modem/router was bad due to a lightening strike when I was at work. I had the cable company replace the modem/router and problem fix. Four: I really did have a bad nic....and that does not happen very much these days. But still it can happen...even on good days. Hope this helps you out a little.