I have DSL, which of course uses standard copper phone lines. (All 4
wires, or just the red and green?)

Phone line out, DSL line in. Phone is always busy to callers from
outside. No dial tone for me, just silence.

How can this be?

Because some of my phone jacks weren't working, about 10 years ago, I
disconnected the line from the NIC to the basement, and ran a line up
the front of the house to the second floor, though the spare b'room and
to the DSL modem in the office. This also meant, even when I had
dial-up, that the computer got the freshest phone signal in the house.

The problem is probably where the round white solid 4-conductor phone
wire goes between the window and the window frame.

But my question is, how can the phone line be shorted while the DSL
works fine???. Aren't they both using the same 2 wires? (even though
there are 4 wires.)



BTW, I used to use thinner wire, but I've been using this stuff for the
last two years. I'm already planning to buy some shielded wire, to
replace the current round phone wire, so I can close the window better.