Hello,

Thank you for the issue report. The exception seems to be the same as in this previous case:
https://forum.prosysopc.com/forum/opc-ua-java-sdk/opc-ua-client-java-io-ioexception-duplicate-extensions-not-allowed/

If you could find the certificate of the server from the trust store of the other client applications, please check it out yourself or send that to us by email, so that we can try to verify the issue.

Unfortunately there is no way to overcome this. You will need to contact the server manufacturer and tell them that they are using invalid certificates.

No, this is not related to the processor architecture of your computer.

The issue is that the server sends an incorrect application instance certificate. Every OPC UA application has unique application instance certificate. These certificates are used to authenticate the applications and secure communication.

The issue is that the server’s certificate does not follow the RFC 3280 rules that specify the usage of certificates. You should report this issue to the server application vendor.

We cannot easily make a workaround ourselves because this check is not in our own code. This certificate checking functionality is standard functionality of the Java language. And actually there’s no point to start working on this: the Java implementation is correct and works according to RFC 3280.