Odd router problem - Wireless works, wired doesn't

A friend of mine has an almost new TP-Link router. It worked fine with a wired connection to his PC XP desktop and WiFi connection to new apple laptop for a few weeks.

Recently though the wired internet connection stopped working, but WiFi still works fine from the apple laptop. Neither the apple laptop nor the PC desktop work when plugged directly into the router, with different cables.

I looked through the admin pages and couldn't see anything obvious. When you plug a cable in the light on the router goes on, but DCHP on the router doesn't see the computer, and the windows machines never get an IP in the 192.x.x.x range. I forget the IP the windows machine took, but it was in the range that windows takes on automatically if it's not connected to a router.

My conclusion is the Ethernet ports on the router have somehow failed. Can anyone think of what else it could be?

tim wrote in post #14689969
My conclusion is the Ethernet ports on the router have somehow failed.

Sounds like it. Time to spend $50 on a new router. Of course, I'd do a hard reset first just to make sure.

tim wrote in post #14689969
My conclusion is the Ethernet ports on the router have somehow failed. Can anyone think of what else it could be?

Sounds like it.
You can flash the firmware in the TP Links to an open source version (ask Momentz) that would make totally sure it is a hardware failure.

But based on what you've done to test, then I don't think it could be much else.
Send it back


On a different note, I have a TP-Link and its the most stable and reliable router I've ever used.

Only thing I can think of is the set connection speed. Try forcing a particular speed and turn off auto.

Thanks guys, I'll just have him take it back, but the genius didn't keep his receipt. If he can't exchange it I'll suggest the connection speed and firmware things.

I'd start by defaulting the unit to factory & see if it changes things - it's possible the dhcp servers' been disabled inadvertantly for the wired side (the windoze machines default to 169 addresses when can't find a dhcp server)

Another thing to do is install wireshark on the wired P.C. & capture traffic while a wireless machine is busy doing stuff. You may be able to see broadcast traffic from wireless machine & that'll tell you at least half of the ethernet port's running. If you can see traffic, then try hard-setting an I/P address on the P.C. in the same range as the traffic.


If the router's Gigabit capable, then be aware that Gig uses all 8 wires in the patchlead, so it only takes one wire (be it in patchlead or router) to go duff then you're firewalled...

Thanks Joeseph. My friend has no idea what an IP address is and my time is worth too much to me to mess around with a $100 router. I'll suggest he reset it, then replace it.

I'd tell him to do a factory reset several times. I've got a linksys router that doesn't play nice sometimes and it takes several resets in a row to get it to work again.