We have been using an OPC HDA interface and it has suddenly stopped working. It has been working based on the defined scan classes to pull data from the OPC HDA server, but we are finding it has stopped. When we restart the interface it does a complete history recover for all of the scan classes but then stops getting data. The service is still running and I see no errors in the log window. The OPC Server has been verified to still be running and serving data via testing with the OPC HDA test tool (Pi and Matrikon versions.).
All of the tags just stop getting data.
Does any one have suggestions on how to troubleshoot this issue further?