Message type: E = Error
Message class:  HRPAYAT_MBGM - Messages for mBGM Functionality 
Message number: 018
Message text: Payroll results exist: No mBGM generated
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The SAP error message HRPAYAT_MBGM018 indicates that payroll results already exist for the employee in question, which prevents the generation of a new mBGM (mass data transfer) for payroll processing. This error typically arises in the context of payroll processing in the SAP HR module, particularly when dealing with mass data transfers or updates.
Cause: Existing Payroll Results: The primary cause of this error is that there are already payroll results recorded for the employee in the system. This means that the payroll has already been processed for the specified period, and the system does not allow for a new mBGM to be generated for the same period. Incorrect Configuration: There may be configuration issues in the payroll processing settings that lead to this error. Data Integrity Issues: There could be inconsistencies or issues with the employee's master data or payroll data that prevent the generation of new payroll results.
Solution: Check Payroll Results: Verify if
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