Newbie question: We discovered that we had a value in sys.event_notifications.broker_instance that did not correspond to the value of sys.databases.service_broker_guid for any existing database. We were unaware of this for some time. Are there any error
messages generated by Service Broker when this happens or is does it just not work?
Have you got the detail error message in your case? If the Service Broker GUID didn't match sys.database services_broker_guid, we will encounter the following issue:
Cannot enable the Service Broker in database " " because the Service Broker GUID in the database (xxxxx) does not match the one in sys.databases (xxxxx)
To solve this issue, we can run the following command to reset the service broker:
ALTER DATABASE XXX SET NEW_BROKER WITH ROLLBACK IMMEDIATE