How do I add a "spatial reference" to a shapefile in ArcGIS Pro?

[StephanieDonoghue1]

I was given some shapefiles. One of them has spatial reference information if you go into properties and it works correctly. The rest have no spatial reference listed, and I don't see anywhere to click to add this information. I'm running on the ArcGIS Pro free trial, so I'm wondering if the free trial has this limitation or if there is another place to add/revise this for the shapefile.

[Robert_LeClair · Accepted solution]

Stephanie - shapefiles are notorious for missing the *.prj files (projection files).  To create a *.prj for each shapefile, you can run the Define Projection geoprocessing tool.  It does require that you know what the projection is in the first place.  If the shapefiles with the missing *.prj file matches up with a known coordinate system in your map view, then you can use that projection.  Hope this helps!

[StephanieDonoghue1]

That did it! Thank you so much!