On Saturday we had planned DB maintenance where we failed over all of our instances to their corresponding correct primary node. In doing so all of the web/windows services terminated as they couldn't connect to SQL, which is totally understandable. But while all the services where stopped the same error (bar a different GUID) came back and was populating the error log 6 times a second.

I checked the message broker logs and nothing was being populated in them like the first time this happened, which is understandable as the message broker service was stopped, so I dropped the queue/service/procedure from the database and the error stopped populating the log.

Now the question is, why would the queue/service/proc be called and cause the error, when the calling service is down?