Message type: E = Error
Message class:  FICODIAN_CUST - Messages for DIAN Magnetic Media Customizings 
Message number: 026
Message text: Enter Tax on Sales/Purchases Code.
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.
To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.
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The SAP error message FICODIAN_CUST026 typically indicates that there is a missing or incorrect entry for the "Tax on Sales/Purchases" code in the system. This error often arises during the posting of financial documents, particularly when dealing with transactions that involve tax calculations.
Cause: Missing Tax Code: The tax code required for the transaction is not maintained in the system. Incorrect Configuration: The tax code may not be properly configured in the tax settings. Transaction Type: The transaction type being processed may not be compatible with the tax code being used. Master Data Issues: The customer or vendor master data may not have the necessary tax information.
Solution: Check Tax Code Configuration: Go to the transaction code OBYZ (or similar, depending on your version) to check the configuration of tax codes. Ensure that the tax code you are trying to use is defined and active. Maintain Tax Codes: If the tax code is missing, you can create or maintain it using
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