Based on Appeon Community and SAP Community insights, the most frequent causes are: 1. Unregistered COM/OLE Control

When connecting to the C# object, use the correct ProgID (e.g., NETS.NETS ), as shown below:

Follow these chronological diagnostic steps to isolate why your external object function is failing:

An mismatch between the PowerBuilder IDE version used to compile the app and the runtime DLLs installed on the client machine will trigger unpredictable memory faults.

Copy the entire application folder from the network to the local C:\temp . Run it from there. If it works, the issue is network latency, permissions, or path length.