Diagnosis
One material exists several times in the material list. You haveassigned this material to the same operation or phase more than once.

Procedure
Check the material assignments at the operations and phases.
Check whether you can combine the material into one item in the bill ofmaterial (BOM).

Note
In Customizing, you can define how the system is to treat this systemmessage. To do so, go to Customizing for Production Planning -Process Industries and choose Master Data -> MasterRecipe -> Settings for the Task List Type -> DetermineSystem Message Features.
Note that this message is displayed only if you have set the type W
(warning). With all other message types, the message is notdisplayed.