Message type: E = Error
Message class:  HRPAYCH_QST21 - Messages for Withholding Tax 
Message number: 020
Message text: Table &1 (PerNo: &2) Before Calculation Step:
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The SAP error message HRPAYCH_QST21020 typically indicates an issue related to payroll processing in the SAP Human Capital Management (HCM) module, specifically in the payroll calculation process. The error message suggests that there is a problem with the specified table and personnel number before a calculation step is executed.
Cause: Missing Data: The personnel number (&2) may have missing or incomplete data in the relevant infotypes or tables that are required for payroll calculation.
Configuration Issues: There may be configuration issues in the payroll schema or rules that are preventing the calculation from proceeding. Incorrect Table Entries: The specified table (&1) may have incorrect or inconsistent entries that are causing the payroll calculation to fail. Authorization Issues: The user may not have the necessary authorizations to access the data required for the payroll calculation.
Solution: Check Infotypes: Verify that all necessary infotypes for the employee (personnel number &2) are correctly maintained and contain valid data. Common infotypes
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