Message type: E = Error
Message class:  SLS_LORD - Lean Order Prozess 
Message number: 010
Message text: External document category reference '&' is not supported
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.
To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.
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The SAP error message SLS_LORD010 indicates that there is an issue with the external document category reference in the system. This error typically arises when the system encounters an external document category that is not recognized or supported.
Cause: Invalid Document Category: The external document category reference specified in the transaction or configuration does not exist in the system or is not defined correctly.
Configuration Issues: The document category may not be configured in the relevant customizing settings in SAP. Data Entry Errors: There may be a typographical error in the document category reference being used.
Solution: Check Document Category: Verify the external document category reference being used. Ensure that it is correctly spelled and matches the expected format. Configuration in SAP: Navigate to the relevant customizing settings in SAP (usually found in the IMG - Implementation Guide). Check the configuration for external document categories under the relevant module (e.g., Logistics, Sales and Distribution). Ensure that the document category you
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