Symptoms
If a user clicks on a link to an action item that has now expired eg moved on or actioned by someone else, they correctly get an error message.
Is there a way to modify that error message in the server set up to something more user friendly?
Diagnoses
This can be done via rules.
Resolution
On the formview that throws the error, add an initialize rule.
Check to see if an error message has been raised that starts with the displayed error.
If so, show a message to the user.
