No ethernet connection since recent power down

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No ethernet connection since recent power down

Hi,

I have an early 2008 Mac Pro running Yosemite. I connect to the internet through an ethernet cable to a time capsule, and have never had any problems until now.

I went away for a few days over Christmas, and turned off and unplugged the Mac Pro and the time capsule whilst I was away. Since I got back, the ethernet cable shows as 'not connected'. I've tried rebooting/disconnecting everything in various orders. I get the green light on the back of the time capsule when I plug the cable into the Mac Pro. I've tried both ethernet slots. The same cable works fine on another computer. I've reset the PRAM and checked all the settings which are still automatic.

Any ideas how I can fix this? Very frustrating!

Many thanks,

Stedders

Mac Pro, OS X Yosemite (10.10.1)

Posted on Dec 27, 2014 4:16 PM

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Answer 1

Dec 27, 2014 4:59 PM in response to stedders

Intel-based Macs: Resetting the System Management Controller (SMC) - Apple Support

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Answer 2

stedders Author

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Dec 28, 2014 1:14 AM in response to Grant Bennet-Alder

Hi,

Thanks for the suggestion. I had sort of unwittingly tried this in that I powered everything down for fifteen minutes or so in case that worked.

Anyway - I've just tried it exactly as specified in the link and it has made no difference. I've now got the Mac Pro plugged into an Airport Extreme via a long cable and the original cable via the time capsule. Both have the green lights at the router end, but both show as not connected.

Any other ideas?

Thanks,

Stedders

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Answer 3

lllaass

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Dec 28, 2014 2:11 AM in response to stedders

What properties/values are listed ins Network Prefernces>Ethernet. A screen shot would be nice

Try signing in as another user.

Try setting up a different location

Using network locations (Mac OS X v10.6 and later) - Apple Support

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Answer 4

stedders Author

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Dec 28, 2014 4:06 AM in response to lllaass

Tried logging in as a different user and that made no difference.

When I tried to create a new location, it didn't have either ethernet port listed.

Here are a few screenshots - let me know if there are more specific ones that would be helpful.

Many thanks,

Stedders

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Answer 5

lllaass

Level 10

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Dec 28, 2014 4:16 AM in response to stedders

Inspect the Ethernet port on the Mac for abnormalities. Compare with ones that work.

Reset the PRAM

About NVRAM and PRAM

Does the Ethernet port show in System Report?

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Answer 6

stedders Author

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Dec 28, 2014 4:43 AM in response to lllaass

Both ethernet ports look ok. I'd done a PRAM reset already but tried it again to no avail.

Yes, both ports show - here's a screenshot from the System Report.

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Answer 7

lllaass

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Dec 28, 2014 4:51 AM in response to stedders

What shows under Hardware>Ethernet Cards in System Report?

You are showing under Network

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Answer 8

stedders Author

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Dec 28, 2014 4:59 AM in response to lllaass

Ah, sorry. It says 'This computer does not appear to have any PCI Ethernet cards installed.'

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Answer 9

lllaass

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Dec 28, 2014 5:11 AM in response to stedders

That means the OS can find the Ethernet hardware.

If you boot to Recovery

OS X: About OS X Recovery - Apple Support

can you connect to the internet. You can connect for Help and some other things

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Answer 10

stedders Author

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Dec 28, 2014 5:28 AM in response to lllaass

No, it doesn't have wifi so ethernet was my only way of connecting. I also don't seem to be able to run the hardware test (holding d doesn't do anything).

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Answer 11

lllaass

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Dec 28, 2014 7:56 AM in response to stedders

For hardware test:

Using Apple Hardware Test

In Recovery, Ethernet will automatically connect. So it you can't connect to internet that means that even with the drivers in Recovery it can't connect. I suggested Recovery since maybe drivers in the regular OS got corrupted or something.

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Answer 12

stedders Author

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Jan 8, 2015 4:14 PM in response to lllaass

Hi,

Sorry, been away for a week or so with work and so not had chance to investigate further.

Frustratingly, when I got back and turned my Mac Pro on, all is normal again. Both ethernet ports work. In one sense I'm delighted it's all working. On the flip side, I don't know if I turn it off and back on again whether it will work next time!

Anyone have any suggestions as to what might cause this sort of intermittent fault?

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Answer 13

stedders Author

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Feb 2, 2015 4:50 AM in response to stedders

So the working part above was short lived. Back to having no ethernet connection again.

If I boot to recovery, under Network Utility I have no ethernet connection to test, and no internet connection to do anything with. For some reason the hardware test doesn't seem to want to work.

Anyone any other ideas? Really appreciate some help with this!

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