SAP Message VSB315 - Verification step incomplete (IDocs not processed yet)

Diagnosis
The processing step should have been started for a transfer for whichthe verification step is not complete:
Transfer was blocked when IDoc &V2& should have been processed in theverification step.

System Response
The processing step can only be started when the IDoc has beenprocessed.

Procedure
Check whether the IDoc is still in the EDI inbox and has status 51. Ifthis is the case, you have to retrigger processing of the IDoc.
If the IDoc is in the EDI inbox and already has status 53, then you haveto restart the verification step for transfer &V1& that contains theIDoc.
Note:
Using transaction WE02 or WE05, you can list IDocs and check theirstatus. IDocs with status 51 that are incorrect can be rescheduled forprocessing using transaction BD87.