Problem: Features disappear from a layer when importing symbology from another layer
When importing symbology from one layer to another layer in ArcMap, some of the features are not displayed in the target layer of the current map document. Symbology can be imported from an ArcGIS layer file (.lyr), a layer in the current map document, or an ArcView 3 legend file (.avl) using the Import button on the Symbology tab of the Layer Properties dialog box, or the Apply Symbology From Layer tool from ArcToolbox > Data Management Tools > Layers and Table Views.
This issue may occur due to one of the following reasons:
• Symbology in the source layer does not match the symbology in the target layer. For example, polygons cannot be symbolized with symbology used for points.
• The symbology between the target and source layers match, but the symbology definitions between the two layers do not match. For example, the feature class values are not the same as the values specified in the symbology.
Solution or Workaround
Modify or create a symbology layer with values identical to the source layer symbology.
• If the symbology in the source layer does not match the symbology in the target layer, ensure the symbology geometry type (point, line, or polygon) in the source and target layers are the same.
• If the symbology definitions in the source and target layers are different, ensure the definitions (such as unique value renderer) in both the layers are identical.
- ArcGIS Help - Importing symbology from another layer
- ArcGIS Help - Apply Symbology From Layer (Data Management)