I have two scripts that can create the Journal. One from a User Event and one from a Map Reduce. For some reason on the map reduce an unexpected error occurs when saving the journal. When I try to do it through the User Event it works fine. Anyone have an idea what would cause an unexpected error when saving a Journal Entry? Have been through SuiteAnswer and I know the periods are open and the dates are right etc.

have you compared that the JE being saved is exactly the same in the UE and MR case?

Yes I have which makes it all the more mysterious

in my experience, MR scripts are the least reliable of all script types. So it is possible that this is some sort of anomaly with MR scripts. Worst case you might try deleting/redeploying. That's a 'nuclear' option but I have seen it work for other people.