Message type: E = Error
Message class:  FKKINV - Invoicing in Contract Accounts Receivable and Payable 
Message number: 140
Message text: ***** Source document category/source document number &1 /&2
Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.
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The SAP error message FKKINV140 typically relates to issues in the invoicing process within the SAP Convergent Invoicing (CI) module. This error message indicates that there is a problem with the source document category or the source document number specified in the transaction.
Cause: The error can occur due to several reasons, including: Invalid Source Document: The source document number or category specified does not exist or is not valid in the system. Document Status: The source document may be in a status that does not allow it to be processed (e.g., it may be blocked or already processed).
Configuration Issues: There may be configuration issues in the invoicing settings or document types that are causing the error. Data Inconsistencies: There may be inconsistencies in the data related to the source document, such as missing or incorrect entries.
Solution: To resolve the FKKINV140 error, you can take the following steps: Verify Source Document: Check the source document category and
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