Sunday, August 01, 2004

Received Unexpected Message Type '' in Orchestration 

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.

About the Author

You may be wondering who I am (or may not!), but I've been in the industry 16+ years working on a variety of systems from IBM mainframes as a CICS systems programmer, to developing on Unix and Windows based systems. At the moment, I'm currently working for a Microsoft Gold Partner in the UK called Solidsoft who specialise in systems integration using BizTalk Server. My position is generally dictated by what I'm doing, but normally as a solutions architect/consultant helping clients with their integration projects involving, yes you guessed it: BizTalk Server.

Disclaimer: all the views expressed here are my own and do not necessarily represent the views of Solidsoft Ltd or indeed any other company.