After some time now I have, with assistance from others, determined that a 'supposedly' 3-way switch installed in our house was mis-wired from the beginning. The switch that 'should' be the 2nd one is in a box of outdoor lites, with the 4-wire from the box goes to the outside lite ...... rather than to the other proper 3-way switch box, located inside.

So this leaves me with a question.... is there anyway this can be corrected? The house is built, and the existing cables are of course behind drywall, etc.. The 2 proper switches are on separate walls also.

Does any one have any ideas????