I was asked to provide either the OPC DA ProgID or OPC HDA ProgID. How do I know if my OPC Server is OPC DA and/or HDA Capable? where do I look for these information?
The information is in the server's documentation.
You can also install the server and then use OPC DA / HDA client to browse for servers on the computer, and check if you see it in the list. This will also typically show the ProgID.
You can also install the server and then inspect the Windows registry. There are entries for component categories. OPC Specifications tells you what are the categories (CATIDs) for OPC DA or HDA servers (plus the categories have descriptive names). The entries for the server will be under the respective category, if the server supports it.