Sunday, August 01, 2004
This was an error that came up recently on a project with a client in sunny Rochdale in the UK. Basically, the orchestration failed with the following error message:
Received unexpected message type '' expected message type '%s'
In effect, orchestration had received a message that had not been resolved to a message type, hence it was unable to understand it. The %s placeholder contained the name of the message type that it was expecting.
This was quite confusing at first because the message that was being returned to BizTalk by way of a solicit-response port was correct according to the schema. Everything looked as if it should match up!
After scratching our heads for a bit, we discovered that the response properties of the solicit-response messaging port was using the Passthru pipeline. This pipeline will not resolve the incoming message against a message type stored in the database! Changing the pipeline to the XMLReceive pipeline did the trick, and orchestration was able to receive the message as a response correctly.