Since you can go 100 meters with CAT5, that's rarely an issue. In fact I've gone double that from a switch to another switch in a single run.
My bet is your wiring pairs are incorrect.
Bob
I recently attempted to network a home running cat 5. I have done this before in apartments but never in a house. I was running cabling for a second floor bedroom to the router that is located in the 1st floor living room. For some reason I can't get the connection to work properly. I have a line tester and all wires test fine. But when I tried to connect the PC to the router, NOTHING! I tried different NIC's but still no luck. Is there a different type of cat5 I need for longer runs? If the cat 5 cable is next to a electrical cable could there be interference? But if that was the case then why does my tester show both ends working fine? PLEASE HELP!!!

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