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.

In some situations, 'BrowseDataNodes' does not complete within 20 seconds.

05 Apr 2019 06:40 #7298 by support

I will start from the end of your report - the part about bxsdk32.dll. This seems related to a 3-rd party product that is included in QuickOPC and takes of "virtualization" of some dependency files (such as UA Certifiate Generator), so that they do not have to be pre-installed on the machine. We have encountered problems with this library from time to time (seldom, but still). So, first thing I'd suggest to do, is to make sure that the "bxsdk32.dll" problem is not causing further issues down the road. To do, so, there is a way to turn off this "prerequisite boxing". Instructions are here: .

Only if the problem persists then:

Yes, allocate more than 20 seconds. In fact, for the worst case, we need to allocate more than 10 minutes, because in the rare case, this is the default value of the longest timeout in effect (OperationTimeout). And, we need to know whether BrowseDataNode returns then - and if it does return with an error (exception), then the details of that error. That may bring the information needed already. If not, we can proceed by obtaining detailed traces and logs (do not do that now, I would send instructions if we come that far).

Best regards

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

  • tsommers
  • Topic Author
  • Visitor
  • Visitor
04 Apr 2019 19:31 #7297 by tsommers

We recently updated our product from version 5.34 to 5.54 of QuickUAOpcClient. In the first installation for one of our customers, we observe the following strange behavior:
- When our program starts the first time, everything is working fine
- When we restart the program, the method BrowseDataNodes uses more than the 20 seconds we have allocated for this task. For this reason, the program fails to connect to the OPC Server. There are no exceptions, the program just 'hangs' on the call to BrowseDataNodes. In the initial start of the program, this call takes about 3 seconds.

The program is connecting to a local opc-server (phoenixcontacts). I am not able to reproduce this behavior on my machine where I currently use a Kepware OPC server. We did manage to reproduce it on a test-machine with the same setup as our customer. But after playing around with old and new versions, we were suddenly not able to reproduce the error anymore. Except for running both the old and new version, we did not do any changes.

My question is: What can the reasons be that makes 'BrowseDataNodes' take so long time on some machines (and even when it do happens, it does not happen every time we run the program)? It would seem like the OPC server does not respond in a timely manner, but there are no indications that it is in a bad state.

In some of the attempts we have seen an exception which basically says that it fails to create a file named bxsdk32.dll in C:\Windows. This exception does not come every time so I am not sure if this is related.

I will test with a version where I allocate more than 20 seconds to see if BrowseDataNodes is timing out or throwing an exception. But apart from this I am running out of ideas of what I can try. Any input is most welcome.


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

Moderators: support
Time to create page: 0.169 seconds