2455540 - No Element found in NWA Identity Management

When searching for a user in Identity Management within the NWA, you receive the error 'No Element found' even though this user exists in datasource/UME.

Within the defaultTtrace file, you can see the below error:
failed to fetch key from ResourceBundle
[EXCEPTION]
java.util.MissingResourceException: Can't find resource for bundle java.util.PropertyResourceBundle, key XX_XXX_XXX

SAP Solution Manager 7.2
SAP Netweaver AS Java 7.4

SAP Netweaver 7.4, SP 12, J2EE-APPS, NO Element found, NWA, Identity Management, user search , KBA , BC-JAS-SEC-UME , User Management Engine , Problem