Diagnosis
Unit costings are only possible in orders/WBS elements where planintegration is not active.

System Response
Choose the paths shown to check whether the plan integration indicatoris set:

• in an order type

(Controlling -> Overhead cost controlling -> Overhead cost orders ->Order master data -> Define order types

• in a project profile

(Project System -> Project planning -> Costs -> Basic settings ->Activate plan integration in the project profile.