Message type: E = Error
Message class:  FKK_ID_XX_SAFT - SAFT message 
Message number: 050
Message text: Main transaction and subtransaction are not specified
The system issues an error message and will not allow you to continue with this transaction until the error is resolved.
To identify third-party invoices, we recommend that you specify the main
transaction and subtransaction in this Customizing activity under
<LS>Define Extraction Rules: Third-Party Billing</> instead of
specifying individual business partners under <LS>Rules for Third-Party:
Additional Parameters</>.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message FKK_ID_XX_SAFT050 indicates that the main transaction and subtransaction are not specified in the context of a financial transaction, particularly in the area of contract accounts receivable and payable (FI-CA). This error typically arises when trying to process a transaction that requires specific identifiers for the main transaction and subtransaction, but these identifiers are missing or not properly configured.
Cause: Missing Configuration: The main transaction and subtransaction may not be defined in the system configuration. Incorrect Transaction Data: The transaction data being processed may not include the necessary identifiers. Data Entry Error: There may be a mistake in the data entry where the main transaction and subtransaction fields are left blank. Custom Development Issues: If there are custom developments or enhancements, they may not be correctly handling the transaction data.
Solution: Check Configuration: Navigate to the configuration settings for the main transaction and subtransaction in the SAP system. Ensure that the main transaction and subtransaction are
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