Automation Wrapper Dll

Thanks for your reply.How shuld I declare GlobalOPCItems???Iv´e been trying Dim GlobalOPCItems(0 To 2) As OPCAutomation.OPCItems. But not sure about this.When I run the form, I can find my installed OPC Server in the combobox but when I try to connect it get'OPC-Server connection Failed: Not possible to convert an object of type OPC.Automation.OPCServerClass to type OPC.Automation.IOPCGroups'(Get the message in swedish so not 100% sure of the translation).Hopefully you can help me with this.Regards/edmund.

There are several threads on this forum dealing with the OPC Automation wrapper, so I thought I'd throw in my two cents.Some important background to know about the Automation wrappers and versions. There actually is a 'General' OPC interface dll. It's called the Automation Wrapper, or OPCDAAuto.dll.

When the first OPC DA specifications were released, the OPC Foundation did not wish to support complied applications, so the source code for the OPCDAAuto.dll was supplied to all OPC members. Each vendor then recompiled the code under their own GUID (for example Rockwell renamed it RSiOPCAuto.dll). In November of 2005, the OPC Foundation decided to take the responsibility of maintaining various applications (DA Wrapper, Compliance tests, proxy stubs etc). All the bug fixes various vendors had applied over the years was compiled and the OPC Foundation released the 'official' OPCDAAuto.dll v2.02. Many vendors already were supporting 'their' wrapper so continue to ship the vendor branded version.Version 2.02 of the automation wrapper has been tested with VB.NET on Win2000 and WinXP. You can read the details on the Foundation website atIf you are an OPC Foundation member you can download the files directly.

Automation Wrapper Dll 1

If you are an end user who is not a member, you need to get the binaries from your OPC Server Vendor.Here's some additional information from the OPC Foundation supplied ntoes: It is important to note that both the DA Automation Wrapper and the OPC.NET API allow.NET based OPC client applications to communicate with existing COM based OPC servers. However users should keep in mind that the DA Automation Wrapper was intended to used only as a way to facilitate porting of existing VB 6.0 applications to VB.NET. I used Martin's code and received the following error:Exception from HRESULT: 0xC004007System.Runtime.InteropServices.COMExceptionWhen I stepped into the Debug everything worked fine until I reached the 'GlobalOPCItems(0) = ' lines.

Opc Automation Wrapper Dll

This is the point at which it errors out. My belief is that I may not be declaring or defining GlobalOPCItems correctly. Some clarificationon this would be helpfull.There are no apparent errors in the code, and my research came up with little in the way of being able to solve this problem. Any assistance would be much appreciated.