home network prob i can not understand 1

[finspell]

I've recently put a cat5 cable from my office to my bedroom approx 35mts through my attic. both ends have just RJ45's for time being. in the office its plugged into a D-Link router and in my bedroom its straight into the laptop. I've tested conductivity on cable and its fine. when i plug in the cable the network continually connects and then disconnects for approx 5 secs on the laptop.
The killing thing is when i connect the laptop to the router using a different cable which is about 5mts long it works perfect.
would the cable from the office to the bedroom be to long? or what is the prob, if anyone can help you could save my sanity!! cheers

 

[jimbopalmer]

I would guess you did not wire the cable such that pins 1 and 2 were one pair, and pins 3 and 6 were another pair.

http://www.duxcw.com/digest/Howto/network/cable/cable5.htm

I tried to remain child-like, all I acheived was childish.

 

[dwestmodesto]

Conductivity doesn't mean a cable is good. Check the color code of both ends of the cable. There is a good picture at this site.

http://www.aptcommunications.com/ncode.htm

If the cable was made not following standards, the shielding given by the twisted pairs will not work and the cable will pick up EMI from any nearby sources. Make sure the cable doesn't run by any flourescent light transformers or other EMI causing devices.
Good Luck
Dave