Solution

Use the Define Projection geoprocessing tool to define an appropriate spatial reference for your data.

If your layer is a query layer, you can modify the query layer directly to define a spatial reference.

1. In the table of contents, right-click the query layer whose query you would like to modify.
2. Click Properties to open the Layer Properties dialog box.
3. Click the Change Query button to open the Edit Query Layer dialog box.
4. Click the Show advanced options check box and click Next.
5. Click the Change button and select an appropriate coordinate system from the Spatial Reference Properties dialog box.

More information

A spatial reference is required to display your data in the correct geographic location. Without a spatial reference, your data may be displayed in an incorrect location or not at all.

How to identify the coordinate system of a map layer. Each map layer has a data source (such as a feature class, raster dataset, and so on). You can right-click a layer in the ArcMap table of contents and click Properties. Next, click the Source tab and scroll through the information on the Data Source panel. The coordinate system details are shown on this panel.

Learn more about spatial references