Professional OPC
Development Tools


Online Forums

Technical support is provided through Support Forums below. Anybody can view them; you need to Register/Login to our site (see links in upper right corner) in order to Post questions. You do not have to be a licensed user of our product.

Please read Rules for forum posts before reporting your issue or asking a question. OPC Labs team is actively monitoring the forums, and replies as soon as possible. Various technical information can also be found in our Knowledge Base. For your convenience, we have also assembled a Frequently Asked Questions page.

Do not use the Contact page for technical issues.

HRESULT: 0X80004005 (E_FAIL) when client.ReadValue(...) is invoked by VB6.exe

07 Dec 2021 08:54 #10431 by
Hello Support

thanks for replying,
I can confirm that HRESULT belong to missmatch between version installed on application server 2020.2 and vb6.exe application compiled with ver. 2021.2 on developing computer.

What I noticed is that seems to be that if you have installed on developing computer 2020.2 together with 2021.2 when you refrence VB6 project to SDK\lib ver. 2020.2 and then confirm with OK closing the declaration interface mask , then if you re-open such a mask the SDL\lib referenced is pointed to the newest version, in my actual situation to 2021.2.

Quite strange :)

Anyway I guess that I will aligned developing computer and application server to the same version, so I should not face anymore this issue.
Or move to newest 2021.3 that I downloaded, not yet installed, yesterday on my deevloping computer.

The following user(s) said Thank You: support

Please Log in or Create an account to join the conversation.

06 Dec 2021 08:24 #10428 by support

I do not know for sure what the reason for the problem is, but it really might have something to do with versioning. In our part, we never specifically generate the E_FAIL error code.

QuickOPC, when used from COM tools (as opposed to .NET) can only safely exist in one version on the computer, for the runtime purposes. (for building COM early-binding apps, at least in theory, you could have multiple QuickOPC versions because what really matters is the version of type library you reference, but for safety, I recommend against having multiple versions of QuickOPC anyway).

Have you uninstalled other versions of QuickOPC? Or, have you tried on a fresh computer where older versions have not been installed?

And yes, you must build with the version you later use for running the app.

Best regards

Please Log in or Create an account to join the conversation.

04 Dec 2021 16:09 #10426 by

I have already developed and used at customer site nr. 4 production machine working with a software solution developed with 2020.2 version and with 2020.2 version on customer server where solution is already running smoothly, I'm asking for a confirmation of right steps to be done.

The point that I have updated the version of OPCLab on my development computer from 2020.2 to 2121.2 and I developed a newest add-on for a couple newest production machines.
So I tested it a bit before going in production, but I faced the following issue "HRESULT: 0X80004005 (E_FAIL)"

I got the error in subject when following code is executed and is reached the instruction Client.ReadValue(.........)

Label1.Caption = " Passo 0 -> prova lettura"

txtChat$ = "ns=6;s=::RicOPCUA:recipeOpcUa.par.RecipeName"
cosa$ = Client.ReadValue(ServerOPCUA$, txtChat$)

If Err.Number <> 0 Then
risp = MsgBox("*** PASSO ZERO >>> lettura Failure parametro: " & Err.Source & ": " & Err.Description & vbCrLf, vbCritical)
GoTo esci
risp = MsgBox("RecipName= " & cosa$, vbDefaultButton1)
End If

So I believe that could depends from missing reference of right SDK library version included in the newest .exe file generated.

I have already prepared the Run-time install.bat file as per documentation

"QuickOPC-2021.2-Windows-Production /TYPE=productioncom"

So could you please confirm that this is ste step to be done to fix the error in subject ?
The previous version of applicationwill continue to work even with 2020.2 , because I will not uninstall, or I have to recompiled with newest 2021.2 ?

See attachments



Please Log in or Create an account to join the conversation.

Moderators: support
Time to create page: 0.067 seconds