Message type: E = Error
Message class:  IDFI_VAT_PR - VAT Pro-Rata 
Message number: 026
Message text: Posting parameter credit tax code is mandatory
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The SAP error message IDFI_VAT_PR026, which states "Posting parameter credit tax code is mandatory," typically occurs during the posting of financial documents when the system requires a credit tax code to be specified for a transaction involving value-added tax (VAT). This error is often encountered in scenarios where tax codes are necessary for proper tax calculation and reporting.
Cause: Missing Credit Tax Code: The most common cause of this error is that the credit tax code has not been specified in the transaction. This can happen if the configuration for the tax codes is incomplete or if the user has not entered the required information in the relevant fields.
Configuration Issues: There may be issues with the configuration of tax codes in the system, such as missing or incorrectly defined tax codes for the relevant company code or transaction type. Transaction Type: The transaction type being used may require a credit tax code, and
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