Error: Unknown Spatial Reference
Adding data to ArcMap which does not have the coordinate system or projection defined displays the following error message:
"Unknown Spatial Reference
The following data sources you added are missing spatial reference information. This data can be drawn in ArcMap, but cannot be projected."
The data does not have a coordinate system or projection defined.
This message is returned for all data types which can be added to ArcMap including geodatabase feature classes, shapefiles, coverages and CAD data, as well as supported raster or image formats which do not have a coordinate system definition.
Solution or Workaround
Identify and define the coordinate system for the data, using the Define Projection tool in ArcToolbox > Data Management Tools > Projections and Transformations, or the data's property page in ArcCatalog.
Refer to the links in the Related Information section below for information on identifying the coordinate system for data, creating a custom coordinate system in ArcMap, and general information about projections, coordinate systems, and spatial references.
If these articles do not resolve the issue(s) contact Esri Technical Support:
- by calling 888-377-4575
- through the Esri Support Center.
- Identify the spatial reference, projection, or coordinate system of data
- Create a custom projection file with units of feet or meters in ArcMap
- Projection Basics: What the GIS professional needs to know