Message type: E = Error
Message class:  FI_LU - Message class for Luxembourg VAT Reporting 
Message number: 001
Message text: Tax code &1 is not allowed
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The SAP error message FI_LU001, which states "Tax code &1 is not allowed," typically occurs in the context of financial transactions where a specific tax code is not valid for the operation being performed. This error can arise in various scenarios, such as during invoice processing, posting of financial documents, or when creating purchase orders. Causes: Invalid Tax Code: The tax code specified in the transaction does not exist in the system or is not configured correctly. Tax Code Not Active: The tax code may be inactive or not applicable for the specific transaction type or company code.
Configuration Issues: The tax code may not be assigned to the relevant tax jurisdiction or may not be set up for the specific country or region. Document Type Restrictions: Certain document types may have restrictions on which tax codes can be used. Company Code Settings: The tax code may not be allowed for the specific company code involved
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