I am glad it works.

Although I cannot yet know the precise reason to the detail, I think we can safely conclude that the problem is with 64-bit registration of the DeltaV OPC Server, or OPCEnum. All other clients you have tried run as 32-bit processes and that's why they work.

Thank you. Now, this was probably with the Demo app, right? May I ask you to try with CLSID once again, now with either your app, or the Demo app (it is in the Examples solution), but built for x86 target?

Are you saying that with the CLSID, it gives precisely the same error ("Class not registered"), or something different? Note: this is very important to answer correctly, otherwise our analysis would go completely wrong way.

OK, it may also be related to the OPCEnum component. In order to determine this, can you please try to use the CLSID instead of ProgID? To do, in your application or in the .NET-based demo, enter the CLSID in place of where you normal use the ProgID (it is marked as "Server Class" argument or field). The CLSID should be used in iys full form, i.e. with "{" at the beginning, "}" at the end, and all the dashed in between the digits etc. You should be able to copy/paste it from the server browsing dialog.


The Online Forums are the preferred way for support. If needed (e.g. if there is a confidential information that needs to be exchanged), e-mail can be used. In such case, please fill in the Contact form on the site, and I will get back to you. Even in such cases, usually the majority can be done over Online Forums, and only the confidential parts over email. We want the Online Forums fill with information that can be use of use to others.

A bunch of questions here please...

Is there any way we can obtain and install the DeltaV server to test it out here? (probably not... just asking).

Have you tried this on more than one computer, and if so, what were results?

What is the ProgID you are using to connect to the server?

Are you using an empty string in place of "machine name" when referring to the local computer, ro are you using something different (such as "localhost")?

From the .NET-based demo app, are you able to browse the OPC servers including the DeltaV server? What kind of information does it display for it?

I still suspect that there may be relation to 64-bits, although you seem to indicate to the contrary. Can you please reinstall the latest *64-bit* OPC Core redistributables, from www.opcfoundation.org/DownloadFile.aspx?CM=3&RI=821&CN=KEY&CI=286&CU=12 ?

Thank you