I installed a new outlet and tied it in with the rest of the outlets in the room in a metal box up in the attic. The house is wired with 14-3 throughout, even on outlets and switches that only require 1 hot. I wired the new outlet with 12-2 before even checking to see what wire the other outlets were using. To make a short story long, two of the outlets are no longer working. I checked the wires in the attic and sure enough the 14-3 that feeds those two outlets is cooked.
My question is do I need to wire up the new outlet with 14 gauge, or did that have nothing to do with the other wire getting fried.