No implementing class registered for the interface
I am getting error - ABAP INTERFACE_REGISTRATION_ERROR : "No implementing class registered for the interface" - when trying to process inbound messages.
Before this error I was getting message - "messages waiting in queue (yellow triangle" . Then i tried to register queues, after that I started getting ABAP INTERFACE_REGISTRATION_ERROR error mentioned above.
Please advice what can be done to resolve this issue.