Can't connect to the internet via Ethernet

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Hi. I had a Mac Mini that worked with this same Ethernet set up, but I just got an iMac and I can't seem to connect to the internet via ethernet. I have tried restarting the cable modem and the computer. I've tried renewing the DHCP Lease but I keep getting the message that it is running with a self-assigned IP address and cannot connect to the internet.
I'm running OS 10.14 with Comcast internet.
P.S. I tried searching for an answer, but I couldn't find anything that helped.
P.S.S. I posted this in the wrong forum, but I couldn't find where/how to delete it there. Sorry.

Karen
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chscag

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Welcome to our forums Karen.

(I took care of your duplicate post by removing it from the wrong forum.)

You need to access your cable modem's internal menu and change it to assigning an IP address using DHCP if it isn't already set that way. Check with the instructions for your cable modem to learn how to access its internal menu. Also, why aren't you using WiFi instead of ethernet?
 
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Did you turn off Wi-Fi on your iMac?
 
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Welcome to our forums Karen.

(I took care of your duplicate post by removing it from the wrong forum.)

You need to access your cable modem's internal menu and change it to assigning an IP address using DHCP if it isn't already set that way. Check with the instructions for your cable modem to learn how to access its internal menu. Also, why aren't you using WiFi instead of ethernet?

I've been using an ethernet connection ever since I set up my Mac Mini. My Mini died (Do NOT unplug a Mini while the computer is still on.) So I got an iMac and now the ethernet can't find an IP address.
My computer is right beside my tv and cable modem and my son said ethernet is faster than wifi. Is that not true? I'm using wifi now, but if ethernet is faster, I'd rather use that.
Karen

- - - Updated - - -
 
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Did you turn off Wi-Fi on your iMac?

I have tried unplugging. Replugging. Turning the modem off.... the computer off. No matter what I do, I get the same message. The ethernet has a self-assigned IP address and cannot connect to the internet. :/
 

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Ethernet is indeed faster than WiFi and if you are close enough to get a connection, you should use that instead of WiFi. Since you can indeed connect using WiFi, that means that the router/cable modem you are connecting to is set up for DHCP on the WiFi at least.

Assuming you've made no changes to your setup, can you please describe how you are connecting your iMac to the Internet? Are you going directly to the cable modem (What brand/model?). Hopefully it's the newer kind that actually is a router as well (unless you have a different WiFi router) and not the OLD pure cable modem type.

Have you tried a different cable between the iMac and cable modem to see if anything happens?
 

IWT


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A direct Ethernet connection with right cable is better than WiFi in that it takes the signal direct from the Modem/router and is much less susceptible to signal dropouts. That said, if your iMac is in close proximity to your Modem/Router, the actual download speed is likely to be more or less the same with either Ethernet or WiFi.

You can compare speed with Speedtest if you wish.

The pundits on the web give conflicting accounts of the pros and cons of each method and also whether you can, or ever should, have both Ethernet cable and WiFi turned on.

As a purely personal opinion, as its a Desktop, I'd always favour Ethernet over WiFi, most especially if downloading large files or during an Update or Upgrade.

You've been given advice on how to deal with the IP address problem and I would pursue that. Also check Ethernet cable, maybe even replace if it's seen heavy duty.

Ian

- - - Updated - - -

Ashwin beat me to it, but I think we are saying the same thing:)

Ian
 
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It doesn't make sense that the only thing that changed was the computer. Yesterday the Mini worked via ethernet. Today the iMac doesn't. Nothing that I've tried has worked. I don't do any heavy downloads so it's not crucial. I just pay extra for faster internet and I wanted to make sure I was getting my money's worth, but this iMac is so much better at everything than my Mini was, I'm in heaven either way! :) Thanks.
 
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I have tried unplugging. Replugging. Turning the modem off.... the computer off. No matter what I do, I get the same message. The ethernet has a self-assigned IP address and cannot connect to the internet. :/
I just meant, that maybe if you turn off Wi-Fi, it will connect using Ethernet?
 

chscag

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I have tried unplugging. Replugging. Turning the modem off.... the computer off. No matter what I do, I get the same message. The ethernet has a self-assigned IP address and cannot connect to the internet. :/

I suspect your ethernet connection via the modem is not setup for DHCP which is why you're receiving a self assigned IP address. The WiFi is working so DHCP there is okay. Ask your son if he knows how to access the modem's internal menu to check the ethernet setup.

Other than that, using WiFi instead of ethernet is not going to slow you down to where you will even notice it. And it eliminates another cable that you can trip over or accidentally disconnect. :)
 
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It doesn't make sense that the only thing that changed was the computer.


Probably because, and as already mentioned, your new iMac has got the incorrect connection settings.

Open your System Preferences then the Network pref pane and set up accordingly with the proper settings.

Selecting Ethernet, it would normally be configured using DHCP.

Your iMac may even help you if you click the Assist me, and use the Assistant option. Then just follow the the directions.





- Patrick
======
 

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Karen:

Give this a shot, one last time:)

With the Ethernet cable attached to your Modem/Router -

Open System Preferences (Click on Apple Icon, second one down = System Preferences)

Now Click on Network

S1.jpg

On the Left side, probably on the top of the list, Click on Ethernet

Look to your right. Where it says Configure IPv4, click on the arrowheads (disclosure triangles) and from the choices offered, choose "Using DHCP"

S2.jpg

Then Click on "Advanced", bottom right and it will open this window:

S3.jpg

Use the red arrows as a guide to the areas to view and set up your settings like mine. Where there are disclosure triangles click on them to select the choices shown in my screenshot.

Worth a try, eh. Nothing to lose.

Good luck.

Ian
 

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