Message type: E = Error
Message class:  HRTNM_MSG - Message class for Training Needs Management 
Message number: 012
Message text: Enter a Cost Category
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The SAP error message HRTNM_MSG012 with the description "Enter a Cost Category" typically occurs in the context of Human Resources (HR) or Personnel Administration modules when a user is trying to perform an action that requires specifying a cost category, but it has not been provided.
Cause: The error is triggered when: A user attempts to create or modify a record (such as a personnel action, cost assignment, or similar) that requires a cost category, but the field for the cost category is left blank. The system expects a cost category to be defined for the transaction being processed, which is often used for budgeting, accounting, or reporting purposes.
Solution: To resolve this error, you can take the following steps: Identify the Transaction: Determine which transaction or action you were trying to perform when the error occurred. Locate the Cost Category Field: Look for the field labeled "Cost Category" in the relevant screen or form. This may be
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