The Location-Allocation solver always needs to have a set of candidate locations to choose from. In real life there are many constraints that will restrict placing a location at the most ideal position. For example there may be a swamp or an already existing structure.
So in case you do not have viable locations where you can locate a facility then you can make a synthetic data set. You can create a grid of points spaced 1 mile apart (or what ever distance makes sense for your problem area) and use them as the candidates or you can use the Create Random Points tool and create points spread out in your study area.
Jay Sandhu
