I came across an existing run that is probably 100 ft or more. I used a Toner Wire Tracker to mark the cable inside of the networking utility cabinet.
I then proceeded to first plug one end into a switch and the other end into a router. No green lights. I tried it directly into a computer and switch. No green lights.
I grabbed my S1007 network cable tester and it only displayed "4&5" as green. I recrimped both ends using T-568B and tried again, still only 4&5 as green. I then made one end T-568A and tested again, and still 4&5 as green.
I'm stumped. I've recrimped both ends several times and the only thing I get is 4&5 green on the S1007 network cable tester. I tested the tester with a known working run and it cycles through the 1&2, 3&6, 4&5, 7&8 cycle.