Thank you, I am glad that the cause of the problem is found.

Great - please download and install the <a href="/LinkClick.aspx?fileticket=W7HYzaSQoWk%3d&tabid=195">OPC Analyzer tool.
After installing, enter any necessary information in the "Category Filter" and "Remote Machine Name" fields, and press the "Refresh" button. Then, select your target OPC server from the "Server" drop-down, and make sure the trace is started (if "TRACE STOPPED" is displayed, press the "start trace" button).
You then need to modify your application to connect to the OPC Analyzer instead of your real target OPC server; the OPC Analyzer acts as an intermediate logger. The ProgID of the OPC Analyzer is "OpcTestLab.OpcAnalyzer.1". You can then run your application, and you should see the trace being collected in the OPC analyzer. Make handnotes of times of any relevant events, such as the time when you have started the application, and when the exception occurred. After you are finished, select File -> Save Trace in the Opc Analyzer, save the .TRA file, and send it to us - ideally, attach it to your reply in this forum.
Note: The OPC Analyzer tool is available to OPC corporate members only, thus the download is only permitted to your user account (you must be logged into our site), and you can only use it for the purpose of troubleshooting this particular problem.

The timeout might be genuine (i.e. it could be the execution in the OPC server that takes so long) or it can be an issue inside QuickOPC. Similar is the situation with the blocking during write statements.
Would you be willing to install OPC Analyzer tool according to our instructions, and collect the information necessary to diagnose the problem? The analyzer acts as intermediary between the OPC Client and Server, and logs the OPC methods calls and callbacks.

[disabling the async method appeared to have solved the problem, though only after some delay; the hypothesis is that there was something blocked inside DCOM or OPC server internals, due to earlier attempts with the async]

Hello,
first, I can confirm that there is no problem with the code itself (except that I cannot verify the validity of the ItemID you have used).


Second, using this line instead:

list.Add(new DAItemValueArguments("", "OPCLabs.KitServer.2", "Simulation.Register_I4", val++));

with our simulation servers works fine, gives no timeout. This means that the servers behave differently.


Before we go into some difficult troubleshooting (e.g. using the Opc Analyzer), I suggest that you try to force the component to use just Synchronous Writes. To do so, add this line (after instantiating the component):

_OpcClient.ClientMode.AllowAsynchronousMethod = false;


Best regards,
Zbynek Zahradnik, OPC Labs

<span style="font-family: "Tahoma","sans-serif"; font-size: 10pt; mso-fareast-font-family: 'Times New Roman'">From:<span style="font-family: "Tahoma","sans-serif"; font-size: 10pt; mso-fareast-font-family: 'Times New Roman'"> M.
Sent: Tuesday, June 14, 2011 3:49 PM
To: Zbynek Zahradnik
Subject: ...
<span style="font-family: "Tahoma","sans-serif"; font-size: 10pt; mso-fareast-font-family: 'Times New Roman'">
Hello Mr. Zahradnik!



In the attachment you will find the project we discussed.


Server:
SIMATIC NET 2006, V6.4
OPC.SimaticNET
(on a different machine as the development system)


Thank you in advance for your support.
Any way to write down to the OPC-Server will help us at the moment (if reading with QuickOPC still works J)


Kind regards
M.