Feature layers are incorrectly symbolized with unique values symbology in ArcGIS Pro

Description

In ArcGIS Pro, when symbolizing a feature layer with unique values, the values are not symbolized or are incorrectly assigned to the 'all other values' symbol class. In addition to this, certain symbol classes are created for symbol values that do not correspond to the feature layer, leading to misinterpretation of data.

Cause

• When new domain values are added to an existing domain, or when domains are created after attributes are assigned to a field, the symbology does not automatically update to reflect the new domain values. As a result, the symbols remain based on the original attribute values.
• By design, only domain values assigned to the field are included as symbol classes. Attribute values that are not associated with the domain are excluded. However, if a domain value is not applied to any feature, it remains a symbol class.
• The attribute values in the field are inconsistent or incorrect due to additional spaces or spelling errors.
• The features are symbolized based on values from a different field.

Solution or Workaround

Depending on the cause, the workarounds provided are applicable.

Use 'Add all values' to include each attribute in the symbol class

1. Open the ArcGIS Pro project.
2. In the Contents pane, right-click the feature layer and select Symbology.
3. In the Symbology pane, on the Classes tab, click Add all values .

Add new symbol classes to the symbology or remove symbol values that are not present in the data

To add new symbol classes for values not included in the domain:

1. Open the ArcGIS Pro project.
2. In the Contents pane, right-click the feature layer and select Symbology.
3. In the Symbology pane, on the Classes tab, click Add unlisted values .
4. In the Select values to add subpane, click Options and click Add new value.
5. In the Value and Label columns, specify the value and label for the new symbol class.
6. In the Symbol column, click Format symbol. In the Format Symbol pane, modify the symbol or choose a different symbol.
7. Click Return to previous symbology page .

8. In the Select values to add subpane, click OK.

To remove symbol classes for values not present in the data:

1. Open the ArcGIS Pro project.
2. In the Contents pane, right-click the feature layer and select Symbology.
3. In the Symbology pane, on the Classes tab, right-click the Value or Label cell for a symbol class and click Remove to remove the symbol class.

Replace the incorrect values in the attribute table

In the attribute table, replace the attributes with the correct values to be displayed as symbol classes. Refer to ArcGIS Pro: Find and Replace for instructions.

Classify features using the correct field values

In the Symbology pane, for Field 1, click the drop-down menu and select the correct field to symbolize.