Message type: E = Error
Message class:  FOT_TDT -  
Message number: 104
Message text: &1 is not defined as a tax rate valid-from date for tax code &2
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The SAP error message FOT_TDT104 indicates that a specific tax rate is not defined for a given tax code on the specified valid-from date. This error typically arises when there is an attempt to process a transaction that requires a tax rate that is not available in the system for the specified date.
Cause: Missing Tax Rate Definition: The tax rate for the specified tax code is not defined for the date of the transaction. Incorrect Valid-From Date: The valid-from date of the tax rate may not cover the date of the transaction.
Configuration Issues: There may be issues in the configuration of tax codes or tax rates in the SAP system.
Solution: Check Tax Rate Configuration: Go to the transaction code OB40 (or SPRO -> Financial Accounting -> Tax on Sales/Purchases -> Basic Settings -> Check Tax Codes for Sales and Purchases). Verify that the tax code in question has a valid tax rate defined for the
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