Our application is built targeting the 4.0 Client Profile, but the first call to read data via QuickOPC was hanging (never returning). The call is inside a Try/Catch block so any error should have been trapped, but no error was reported - the app simply stopped responding to all input and had to be force quit in task manager. Even after installing .NET 3.5 SP1 the calls in our app (and in the demo apps which would now launch) were hanging until I reinstalled QuickOPC, then they all started working fine. I wonder if there is something in the installer that doesn't get installed properly unless .NET 3.5SP1 is present.

Thanks for compliment.
I think that 4.0 does work, but what happens is that because the applications are (intentionally) built against CLR 2.0 (which is used by .NET 2.0, 3.0 and 3.5), it will pick it up by default. It could be seen in your error message that it comes from CLR 2.0; but because the .NET Framework 3.5 was not installed, some required assemblies were missing.
If you build your application, or recompile the apps from source code but retarget the project to .NET 4.0, it will work. The other option may be to keep the app binaries as they are, but configure them to run under CLR 4.0. I think that can be done in the config file of the app; let me know if you need instructions.
The stuff that you see in version 5.20 for OPC "Classic" will be all (or in major part) available for OPC-UA as well, in version 5.21 - we are working on that right now.

I installed .NET 3.5 SP1 and the apps would launch, but freeze trying to read from a server. I reinstalled QuickOPC-UA and the apps are working correctly now. I believe something in the QuickOPC install requires .NET 3.5 SP1 to be installed. The documentation lists 3.5 *OR* 4.0 as a requirement, but apparently only 4.0 does not work.
I use the setup program to install QuickOPC-UA. The setup lists build 1355.1.
Thank you for the excellent support.
By the way - outstanding work on the new 5.2 updates to QuickOPC .NET. I look forward to similar features in upcoming version of QuickOPC-UA (hint, hint).
John

Hello,
some questions:

Do you install the QuickOPC-UA apps using our setup program, or differently?
Can you please identify the precise version and build of QuickOPC-UA? Best way to do this is by re-running the first screens of the Setup and taking the info from there, then Cancel.

In generally you should have .NET Framework 3.5 with SP1 installed, and I do not see it in your list. I will have to specifically test whether missing 3.5 SP1 will cause this error, but installing it should be one of the first things you do. Please let me know if it does not help.
Best regards

Greetings,
I have a computer with Windows XP SP2 (x86) and .NET versions 1.1, 2.0SP1, 3.0, and 4.0 Client Profile installed. When I install QuickOPC-UA on this machine and import my certificate, the two included apps (Demo App and UA Console app) both crash when launching. They both report an EventType of clr20r3 with a "system.io.filenotfoundexception".
Do you have any idea what might be the problem?
Thanks,
John