Message type: E = Error
Message class:  HRPAYAT00 - HR-AT: Messages (General) 
Message number: 201
Message text: End of employment must be entered for chosen dereg. reason (0400).
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The SAP error message HRPAYAT00201 indicates that when processing a deregistration (dereg) reason, specifically reason code 0400 (which typically refers to "End of Employment"), the system requires that an end of employment date be entered. This error usually occurs in the context of personnel administration or payroll processing when an employee is being terminated or deregistered from the system.
Cause: The error arises because the system expects a specific end date for the employment when the deregistration reason is set to 0400. If this date is not provided, the system cannot process the termination correctly, leading to the error message.
Solution: To resolve this error, you need to ensure that the end of employment date is entered in the relevant infotype. Here are the steps to do this: Access the Employee's Record: Go to the personnel administration module and access the employee's record for whom you are trying to process the deregistration. Navigate to the Relevant
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