Message type: E = Error
Message class:  CPWB - General Workbench Messages 
Message number: 152
Message text: Select operation
Before you can execute the chosen function, you have to select at least
one operation. You have not selected an operation.
The chosen function cannot be executed.
Select at least one operation.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message CPWB152, which states "Select operation," typically occurs in the context of SAP's Production Planning (PP) or Capacity Planning modules. This error usually indicates that the system is expecting a selection of operations for a particular task, but none have been selected or available for processing.
Cause: No Operations Selected: The most common cause is that the user has not selected any operations for the process they are trying to execute. Missing Data: There may be missing or incomplete data in the routing or work center that prevents operations from being displayed or selected. Authorization Issues: The user may not have the necessary authorizations to view or select the operations.
Configuration Issues: There could be configuration issues in the system that prevent the operations from being displayed correctly.
Solution: Select Operations: Ensure that you have selected the appropriate operations in the relevant transaction. If you are in a planning or scheduling transaction, make sure
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