Message type: E = Error
Message class:  APPL_MM_PUR_SOS_SL - Messages for Source List 
Message number: 005
Message text: Enter an existing source list number.
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The SAP error message APPL_MM_PUR_SOS_SL005, which states "Enter an existing source list number," typically occurs in the context of materials management, particularly when dealing with source lists in purchasing. This error indicates that the system is expecting a valid source list number, but the number provided does not exist in the system.
Cause: Non-Existent Source List Number: The source list number you are trying to enter does not exist in the database. Incorrect Input: There may be a typographical error in the source list number you are entering. Source List Not Created: The source list for the material or vendor has not been created yet. Authorization Issues: You may not have the necessary permissions to view or access the source list.
Solution: Verify Source List Number: Double-check the source list number you are entering for any typographical errors. Check Existing Source Lists: Use transaction code ME01 (Create Source List) or ME03 (Display Source List) to check if the
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