Lighting, Light Fixtures, Ceiling and Exhaust Fans - Need help....

I am currently remodeling a kitchen and den. In the den there is are two three way switches. Upon disconnecting the three way switch at the beginning of the run I haven't been able to reconnect the switches correctly. Because of the age of the house all the wires are 12/2. At this three way switch there is 12/2 wire from the box, to an outlet, and up to the lighting fixture. Upon connecting the wires in a manner to allow the switch at the beginning of the run, the opposite switch when pressed causes the breaker switch to trip. i've currently got the switch hooked as follows:

All three black wires are in the switch with the outlet black as the common, and all white wires connected together. At the opposite switch there is 12/2 connected with the black in the common and an additional black wired to the switch with the additional white capped off.

I need to know what is wrong with this circuit that is causing the breaker to trip and how to correctly wire this circuit to allow the three ways to work properly.

Any help will be greatly appreciated.

Well, you haven't told us the wiring. We need to know all the wiring at every involved location.

However, mu advice is to rewire this properly using 12-3 and ignore the mess you have. Someone was cheap or ignorant and did not use the proper cable.