Great - I am glad it is resolved

Thank you for your prompt reply.

With your help, I have found the answer to my problem. In my application, I am using System.Windows.Forms.Integration.ElementHost to host a WPF user control that I had created using Version 5.30.1034.1 OpcLabs.EasyOpcClassic. Since it appeared as a separate project in my solution, I neglected to think about updating the references. Once you asked, “Have you started your development with an earlier version,” it got me to thinking and I started looking.

The solution now deploys properly as a ClickOnce application. In response to your “general note,” I have deployed several QuickOPC applications here at the plant as ClickOnce applications. As you stated, it certainly “is not as straightforward as just bundling the executable and referenced assemblies,” but once you have everything configured properly, it seems to work flawlessly.

Thanks again for your help and prompt reply.

Have you started your development with an earlier version? (5.30)? If so, there may be "traces" of the earlier version on your system that can confuse the installation tool. Specifically, please check the following:

- Your GAC - it is versioned, therefore it may contain multiple versions of any single assembly. Make sure there are no assemblies in your GAC with the earlier version number. Use GACUTIL, for a proper version of .NET framework, to view the GAC contents.

- Your project files (for example, .csproj or .vbproj). Do not use Visual Studio to check this, because VS hides some information contained in the files. Open them in Notepad or other text editor, and look for the version numbers in assembly references.

On a general note (and unrelated to this assembly verion problem), I am not sure whether full ClickOnce deployment of applications created with QuickOPC is possible; certainly it is not as straightforward as just bundling the executable and referenced assemblies. Regardless of the installation technology used, there are prerequisites that must be installed as well (such as OPC proxy/stub contained in OPC Core Components, and Microsoft C++ redistributables). Please study the "Application Deployment" chapter in the "Concepts" document (installed with QuickOPC).

Best regards

I created a fairly large WinForm application using both LiveBinding and the EasyDAClient (OpcLabs.EasyOpc.DataAccess). The program works well on my development machine, but when I try to deploy the program (I am publishing it as a ClickOnce Application), I get an error dialog box stating, “Unable to install or run the application. The application requires that the assembly OpcLabs.EasyOpcClassic Version 5.31.1331.1 be installed in the Global Assembly Cache (GAC) first. Please contact your system administrator.”

The answer to this seemed obvious, I went back to my “Publish” settings and chose to include the OpcLabs.EasyOpcClassic.dll in the application files. Now when I publish I get the same error but asking for an older version of OpcLabs.EasyOpcClassic. The error now states, “Unable to install or run the application. The application requires that the assembly OpcLabs.EasyOpcClassic Version 5.30.1034.1
be installed in the Global Assembly Cache (GAC) first. Please contact your system administrator.”

Can you tell me why the setup is looking for this older version of the dll and how do I fix this?

I have attached a screenshot of the two errors for clarity.

Thanks for any help that you can give.