Message type: E = Error
Message class:  CKMLDUVN - Inventory differences distribution messages 
Message number: 501
Message text: Select a line
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.
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The SAP error message CKMLDUVN501 "Select a line" typically occurs in the context of the Material Ledger (ML) or during the execution of certain transactions related to inventory valuation or cost management. This error indicates that the system expects the user to select a specific line item in a list or table but none has been selected.
Cause: No Selection Made: The most common cause is that the user has not selected any line item from a list or table where a selection is required. User Interface Issue: Sometimes, the user interface may not allow for a selection due to a glitch or a temporary issue. Authorization Issues: In some cases, the user may not have the necessary authorizations to select or view certain line items.
Solution: Select a Line Item: Ensure that you are selecting a line item from the list or table before proceeding. Click on the desired line to highlight it. Refresh the Screen:
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