PCo 15.03 / MII 15 SP03 Notification error

I am setting a basic notification in PCo that reports a tag from KepserverEX to MII. Everything seems to be configured and I can query the tags etc in MII but when I click the "View Sample" button in the Notification Test Dialog box I get the following error:

Connectivity framework error : Configuration for notification TestNotificationMessage (00000000-0000-0000-0000000000) not found.

Does anyone know what the issue is ?

I have a transaction created in MII with an input XML parameter parameter called inputXML and I have selected that in the destination tab of the notification. The expression in the notification is just the tag name. Trigger is enabled and set to Always

Thanks in advance for any help you can give.

Kevin