Thank you, I am glad it works. Not quite sure why the GAC resolved it, but with this information in hand, we will investigate further. Are you sure that all necessary assemblies have been deployed alongside your application?

Dear Sir,

this is a problem that has already been reported to us (as documented in this forum thread). We were, however, never able to reproduce it, and are therefore not currently in a position to provide an explanation or a workaround. It is possible that with more information in hand, we would be able to understand what is happening "inside the covers". For this reason, below I am here copying a request for more info which we have sent to another customer (and to which, unfortunately, he has not responded):

I need to bother you with additional questions.

Can you please try [the same] with the demo app?
Can you please capture the call stack at the time of exception?
Can you please add an event handler to the static EasyUAClient.LogEntry event, and capture (and send to us) all the event messages that it provides since the start of the service until the moment of the exception?

I know it takes some effort to do this, but I see no other way to get closer to some solution at this point.

Thank you, and best regards

I have not provided any workaround or solution yet. It is an internal error for which I either need to find a reproducible scenario, or somehow obtain enough information about the internal status of the library on your side. As I could not reproduce it so far (will keep trying), I need to bother you with additional questions.

Can you please try with the demo app?
Can you please capture the call stack at the time of exception?
Can you please add an event handler to the static EasyUAClient.LogEntry event, and capture (and send to us) all the event messages that it provides since the start of the service until the moment of the exception?

I know it takes some effort to do this, but I see no other way to get closer to some solution at this point.

Thank you

Regards

You may have the same or similar error message, however the cause would probably be different, because the original issue has been fixed (and not reverted in 5.35).

Can you please provide as much as possible information, and specifically:

1. Operating system, bitness, and service pack level used.
2. Which language and/or tool you are using.
3. What type of project (e.g. desktop app, Web app, Windows service, ...)
4. Does it happen when you run the program in the debugger? Or outside the debugger? Both?
5. Important: the call stack.
6. Does it happen only sometimes, or always?
7. Do the demo apps (for OPC UA) supplied with the product work well, or do you they also show the same problem?

Thank you