Question : Laptop can't connect through router, but 2 desktops can!  Shows connected to LAN...

Hi!
  I'm using a 4-port wired Linksys router (latest firmware) with Windows XP.  On two ports are my PC's, and on the third my laptop.  The two PC's can get online and see each other just fine, the laptop can't do either (anymore...WAS fine the other day...dunno what happened!).  All on same network place ("HOME"). I've tried system restore, switching to a different port, resetting & unplugging router and cable modem...no luck.  Then tried ipconfig commands...ipconfig /renew gave me the error:
    "an error occurred while renewing interface Local Area Connection: unable to contact your DHCP server. request timed out".
    According to the network connections , I'm connected to a networkat 100Mbps.  All firewalls are disabled.  Also tried switching patch cables.  Even reinstalled Windows XP.
The activity monitor shows packets are being sent, but zero have been received.
Any help appreciated!

Thanks!
Rah,
   rballard34@comcast.net

Answer : Laptop can't connect through router, but 2 desktops can!  Shows connected to LAN...

>The activity monitor shows packets are being sent, but zero have been received.
Tried switching to a known-good cable and switch port?
Sounds like either the cable/switch port's bad or the tranceiver on your NIC.
Check the advanced properties of the NIC and try both 1/2 duplex and AUTO (don't set it explicitly for FULL DUPLEX).