I can share that too many times an installer will use pairs across the RJ45 as 1,2 3,4 5,6 and 7,8. Today after encountering that too many times, I don't suffer any debate but pack up and thank them for the call if they tell me it's right.
I'm having an issue with some Cat 5e cable that I had run for me. We ran a cable from one floor to an office on another floor of my home. The cable goes from wall plate to wall plate on each level. I have a cable modem, and a coaxial connection at each wall plate with the Ethernet.
When I connect the modem upstairs to my router and then to the wall plate to downstairs, I'm able to connect just fine downstairs when I plug my computer to the wall plate. When I reverse this (modem and router downstairs connected to the wall plate, and computer upstairs connected to wall plate) I am not able to connect to the Internet or even the LAN. It is as if the Cat 5e run only works one direction.
I've checked that all the cables are good aside from the run, and I do have checked that I have an Internet connection regardless of where I plug in the modem and router. Any suggestions as to what would cause this and how to fix? I would like to put my modem in either place and have it work. Thanks!

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