I copied my coordinate files into Coordinate folder inside
Users\myuser\AppData\Roaming\Esri\Desktop 10.2\ArcMap\Coordinate Systems\....
The problem arises when I try to project using a custom made Geographic Transformation. When I select the Output Coordinate then in Geographic Transformation (optional) there comes nothing.
Where are the transformation parameters created?
Amazingly, this only happened in one of my laptop. Otherwise, this was not the problem before.