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I have a few layers. The layers have been made by a different company. So
How do I combine them all together so that they have the same coordinate systems?
I already add the layers, right click < Data frame properties < coordinate system. And select a coordinate system. But it shows the same. The layers do not seem to overlap. (For example I pick a river layer at the same place, and I add a road layer also from the same place.) But they don't overlap.
Is it because the size of the layers are different?
Or is the coordinate system from map info is different from the beginning?