SAP Message /BEF/GENERATOR157 - Archive information structure &1 created but not active; no generation

Diagnosis Archive information structure &SYST-MSGV1& has already been generated,but it has not yet been activated. Procedure Open archive administration (transaction SARA). After entering the archiving object, branch to the Archive InformationSystem. Branch to Customizing from the entry screen of the Archive InformationSystem. You activate the structure by entering the archive informationstructure.