AX can sometimes through confusing error messages – this is definitely one of them.
When a user is attempting to save an expense report record on the Enterprise Portal:
A currency to convert to is required to retrieve exchange rate information.
After confirming that the usual suspects such a system currency are properly populated, it is advisable to double check that all of the custom expense report policies are properly configured.
In the screenshot below, the policy is improperly configured:
Whenever an amount is referenced in a policy, a currency parameter must be specified:
The expense report item will now submit properly.