I've been running the same internet setup for almost a year. Nothing has been changed.
Last week I turned on the MBP and it wouldn't connect. I opened the network preferences and even tried the diagnostic and assistant, but the Ethernet connection wasn't even an option.
Of course, I checked the cable connections... contacted the ISP.... and reset their hardware. I know it's not that because I connect to my wifes PC and it works fine.
If I restart my MBP a few times then it will connect. It might take 1 time or 8 but I know it's the MBP.
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