Strategies for dealing with unknown messages
It’s common in HL7 interfaces to set up a default message in the VMD file which will be invoked when an unrecognized message is found. See what to expect in the vmd file.
If you do have messages encountered that are picked up by the default message matching rule it’s easy to choose what to do with them. You can raise an error, log a warning or do whatever you want to do to make it easy to reprocess these messages at a later stage.