Macbook Pro can't see ethernet connection

I purchased the new Macbook Pro on 10/22. And in that three and a half weeks, I've had to return it TWICE because of the same issue. They have been nice enough at the Apple Store and have transferred all files, apps, etc to a new laptop. But yes, same experience -- working away in a business office and all of a sudden the ethernet connection goes out. Since the model is so new, they can't say whether it is a malfunction of the model or a problem (surging) with the ethernet connection at the office I'm working at. So for now, they are just saying that I shouldn't use that port. Meanwhile, several other Macbook users (older model) are working around me with no problem whatsoever. If this happens one more time, I'm taking the Macbook Pro back and will order a refurbished older model.

I would like to know if anyone else has had a problem with the ethernet port so it can be determined whether it is a problem with this new model.

Perhaps try setting the location to automatic, leave the cable plugged in, shut down the MBP, reboot the modem and then turn on the MBP.

Sometimes that does the trick.

yes, i have. i lost my internet connection 2 days ago on my mac book pro. internet access works just fine on my dell p.c.

i have a problem too with the ethernet port, on a new macbook. see details: http://discussions.apple.com/thread.jspa?threadID=1781773
only restarting can bring back the connection.

On some routers, sometimes you need to reboot the router, and then "Release the Lease" and "Renew the Lease" on the WAN section of your router's configuration. It has something to do with the DHCP stuff.

I have the same exact problem. I have already returned my macbook once for this issue and i am going to have to do it again if there is no fix released. I cannot believe this. No matter what i do i cannot get the computer to see my ethernet cable. It keeps saying that the ethernet plug is not plugged in!

I have the same problem too, however this only happens when i try to connect my new macbook pro to my gigabit switch (linksys SD2005). Initially i thought it was a cable problem, i used a cat6 cable, then i tried a cat5e cable with no luck.

I tried connecting my macbook pro with my router (linksys WRT54GL - tomato firmware) and all my cables (cat6, cat5e, cat5) worked!

I then tried the same thing on my mothers new macbook with the same results. The linksys switch is connected to my iMac (1st gen aluminum), and it connects well with my linux box on gigabit speed.
I find it surprising to see this problem on both the new macbook and macbook pro...
Im thinking it's either the firmware or the hardware it's self (i used bootcamp with windows xp and the problem persists)

I am also using a Linksys SD2005 v2.1 which the MBP does not recognize, if I switch the ethernet to a Peplink router it instantly finds the connection, I am not sure if it is because it is a 10/100 switch instead of 1000, I am going to see if I can get another Gigabit switch and test it.

I got the exactly the same thing, I bought a Macbook pro 2.53G/4Gram/230Ghd. three weeks ago, but within one week, the ethernet port couldn't be seen, I called the apple service, they exchanged me a new one.
But after two weeks, just yesterday, the same thing happened again, at first I thought this could be my fault, but coming here, I realized that I must be a fault of design.

To be clear, this post is regarding the issue of the Ethernet port on the new macbook (Late 2008) burning out COMPLETELY. No restarting, plugging, unplugging, pinging, or praying will bring it back, as confirmed by the Geniuses at the Apple Store. If you have issues otherwise, please post a new discussion.

Thank you to those who have documented their cases here as it may lead to a quicker resolve of this potential hardware fault.

My experience is similar, and the workaround I have devised is frustrating. I too am connecting to a gigabit switch. Windows, via BootCamp/VMWare Fusion, sees a 1GB connection (bridged networking). Mac ethernet, when set to automatic or forced to 1000baseT, will not connect (reports cable unplugged). It will sporadically connect, then drop out. It will connect if I turn AirPort on, then disconnect when I turn AirPort off.

The only solution I have found is to manually set the Ethernet to 100baseTX. The switch is seeing me connected at 1000/T, but the MBP reports 100. Speed tests on the Windows side are significantly faster than on the Mac side.

It seems like the hardware is working but something in software/firmware is not?

The list of people having the same problem is getting longer.
See thread here.
http://discussions.apple.com/thread.jspa?threadID=1645716
It's 2008 and this MBP is a very expensive piece of equipment. This should just not happen to all of us.

I've posted a separate question at http://discussions.apple.com/thread.jspa?threadID=1829751 specifically about issues to do with syncing with a gigabit switch.

Cheers,

Joel

Just wanted to add that my unibody Macbook Pro also encountered a dead ethernet port after 4 weeks. No fix available other than exchanging it for another MBP.

Same problem here. Router detects the Macbook Pro, but the Macbook insists that the ethernet cord is unplugged, and no amount of restarting, resetting the network, etc. can change this.