Hi,

We have a couple of OPC UA devices in our lab, all of which have self-signed certificates. When we choose Sign or Sign&Encrypt Security Mode, the self-signed cert is presented and we have the option to accept once or accept permanently. When we accept permanently, the cert is stored in the trusted certs folder.

Now, my understanding is that this cert is the authentication root for all further communication with this device. Meaning, for all further communications, the cert from the device is checked if present in the trusted certs folder and validated. If the certificate expires after say 3 years, What is the behavior here? Would an exception be thrown that communication failed? Or would the user be prompted again to accept the certificate? If so, when the cert is accepted would the expired cert in the trusted certs folder be replaced by the new cert?

Thanks.