Your next job is to check that the wire pairs were done properly in the wall jacks. There are 2 standards and one is for something other than Ethernet and will cause issues like you reported.
Bob
I just moved into a home that has and office. There is a wall plate with a jack to run Cat5e to the upstairs bedroom. I plugged that office wall jack into the router, and the bedroom jack into my laptop and have a perfect connection. My problem is that i need that wire to go to a theater room at a different part of the house (still upstairs like the bedroom). I bought a 50ft cat5e cable and a coupler and connected everything. When i did i dont get a connection. I double checked the wiring and all seemed correct. I then replaced the 50ft cable with a new 50ft cable thinking it was bad but same results. I finally tried a shorter 6ft cable and it worked fine. Any ideas???
Thanks in advance.

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