Unable to delete required fields in ArcGIS Pro

Description

Attempts to delete a required field using the Delete Field tool fail and return the following error message in the Drop Field section:

Error:   
ERROR 001334 Cannot delete required field <value>

Cause

This is by design. Required fields are permanent and cannot be deleted. Refer to ArcGIS Pro: 001334: Cannot delete required field <value>. for more information.

Solution or Workaround

As a workaround, export the attribute table using the Feature Class To Feature Class tool, and remove the desired field.

1. On the top ribbon, click the Analysis tab, and click Tools.
2. In the Geoprocessing pane, search for and click Feature Class To Feature Class (Conversion Tools). The Feature Class To Feature Class window opens.
3. In the Feature Class To Feature Class window, click Parameters.
4. For Input Features, select the layer with the desired attibute table. In this example, the layer is Trails.
5. For Output Location, specify the geodatabase location of the layer.
6. For Output Name, specify a name for the output feature class. In this example, the output name is New_Feature_Class.
7. In the Feature Class To Feature Class window, click Fields. Under Field Map, in the Output Fields section, hover over the required field, and click Remove.
8. Click Run.