Why do layers with the same coordinate system not overlap?
My hypothesis is that your 30 m shift is due to datum difference but that your original shapefiles are correctly georeferenced (each in a different projection system). If selecting a transformation does not improve your accuracy, then I would add a third layer (e.g. a basemap) and try to find out which one is wrong.
How to overlay unprojected Lat and long layers?
Subsequent unprojected lat/long layers will overlay properly, but projected layers won’t. To get them to overlay, you must define the unknown layers’ projections, then also define the Data Frame’s coordinates.
Can you overlay ArcGIS on any other layers?
It should also overlay correctly on any other layers, provided they have a projection defined and that your Data Frame in ArcMap has a projection defined. Although you have set the projection of your 3 other layers by the properties menu in ArcCatalog, you have failed to re-project the data to the proper coordinate system.
How is the coordinate system set in ArcMap?
Coordinate System tab. The Data Frame’s coordinates will be set by the first layer that you open. The various possibilities are displayed in tabular form in a Quick Reference Table. If all layers have defined projections/coordinates, then they should all overlay properly.
Why are the layers not showing up together in ArcGIS?
Projected Coordinate System: NAD_1983_UTM_Zone_14N Projection: Transverse_Mercator False_Easting: 500000.00000000 False_Northing: 0.00000000 Central_Meridian: -99.00000000 Scale_Factor: 0.99960000 Latitude_Of_Origin: 0.00000000 Linear Unit: Meter What I do usually is to restart ArcMap and load the last dataset first.
Can a coordinate system overlap an ArcGIS Shapefile?
Even if your shapefile were in different coordinate system, ArcGIS should project them on the fly so that they overlap properly.