Exceptions are managed in Setup / Usage Rating / Exceptions
UDR exceptions occur when the rating engine fails to rate mediated usage (usage that has been successfully imported). Exceptions logged are displayed here, categorized by their error type. After resolving the issue that caused an exception the usage can be reprocessed (rating can be attempted again) from this screen.
Usage must be mediated (imported) before it can be rated. If mediation is not occurring/successful then there will be no usage to rate/rating exceptions.
The UDR Exceptions panel on the left of this screen lists the types of exceptions that can occur and provides a count for the number of exceptions that currently exist for the exception type in question. Selecting an exception type that has a Count value will show the details of the exception in the Edit UDR Exception panel.
The information in this panel reflects the currently selected exception type. From here you can reprocess (rate) usage in exception and view details on the usage that triggered the exception (date of the usage, identifiers, the source file name, etc.).