Message type: E = Error
Message class:  SD_FREE_GOODS_MSG - Message class for Free Goods maintenance 
Message number: 006
Message text: Condition validity start date is required.
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The SAP error message SD_FREE_GOODS_MSG006 indicates that a condition validity start date is required for free goods in the Sales and Distribution (SD) module. This error typically occurs when you are trying to create or process a sales document that includes free goods, but the necessary condition records do not have a validity start date defined.
Cause: Missing Validity Dates: The condition records for free goods do not have a validity start date set. This is essential for the system to determine when the free goods promotion is applicable. Incorrect Configuration: The configuration for free goods in the pricing procedure may not be set up correctly, leading to missing or incorrect data. Data Entry Error: During the creation of the sales document, the required fields may not have been filled out correctly.
Solution: Check Condition Records: Go to the transaction code VK11 (Create Condition) or VK12 (Change Condition) to check the condition records for free goods. Ensure that
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