Message type: E = Error
Message class:  VK - Pflege und Bearbeitung von Konditionen 
Message number: 426
Message text: No valid cond.type has been defined in the agreement type for tgt table &
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The SAP error message VK426 indicates that there is no valid condition type defined for the target table in the agreement type you are working with. This error typically arises in the context of pricing conditions in sales and distribution (SD) or materials management (MM) modules when trying to process pricing agreements, contracts, or similar documents.
Cause: Missing Condition Type: The condition type that is expected for the pricing procedure is not defined in the agreement type. Incorrect Configuration: The configuration for the pricing procedure or the agreement type may be incorrect or incomplete. Inconsistent Data: There may be inconsistencies in the master data or transaction data that lead to this error. Custom Development: If there are custom developments or enhancements, they might not be correctly handling the condition types.
Solution: Check Agreement Type Configuration: Go to the configuration settings for the agreement type in transaction code SPRO. Navigate to Sales and Distribution > Basic Functions > Pricing >
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