Feature Service attachments created in ArcGIS Desktop are not found in ArcGIS Online pop-ups

Description

Attachments that are published with a feature class from ArcMap to hosted services are not accessible in ArcGIS Online. When the feature service is added to and viewed in the Map Viewer, a feature's pop-up reads 'No Attachments Found', even though the attachments were successfully published from ArcMap. This behavior is unexpected.

Cause

The Object ID field of the feature class used for the feature service is named something other than 'OBJECTID'. For example, the field may be named 'OBJECTID_1' after various manipulations of the dataset. When setting and running Add Attachments to a feature class, the Join Field can be an ObjectID field or any other identifying attribute. This problem occurs when using either option for the Join Field, if the indexed ObjectID field is named anything other than 'OBJECTID'.

Solution or Workaround

This behavior has been reported in NIM090268: 'If an object ID field is called something other than OBJECTID within a file geodatabase with attachments enabled, the attachments are not visible when this data is published to ArcGIS Online.' The workaround for this issue is to re-create the feature class with a new indexed ObjectID field.

1. In ArcMap, add the feature class to the Table of Contents and open the Properties window.
2. In the Fields Tab, uncheck any fields with 'OBJECTID' included in the name.
3. Export the feature class to a location and a new field is created and named 'OBJECTID'.
4. Re-add all attachments and republish the data as a service.