Message type: E = Error
Message class:  FKCHK - Check Repository Messages 
Message number: 323
Message text: System unable to interpret check number &1 numerically
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The SAP error message FKCHK323 indicates that the system is unable to interpret a check number numerically. This typically occurs during the processing of payment documents, particularly when dealing with checks in the Accounts Payable (AP) module.
Cause: Invalid Check Number Format: The check number may contain non-numeric characters or may be formatted incorrectly. Data Entry Errors: Manual entry of the check number may have introduced invalid characters or spaces.
Configuration Issues: There may be issues with the configuration of the payment program or check management settings in SAP. Database Issues: The check number may not exist in the database or may have been deleted or altered incorrectly.
Solution: Check Number Validation: Verify that the check number being used is indeed numeric and does not contain any letters, special characters, or leading/trailing spaces. Ensure that the check number is within the valid range defined in your system. Review Payment Document: Go to the payment document in question and check the details
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