Message type: E = Error
Message class:  SIAO_DEL - SIAO: Digital Signature Angola 
Message number: 107
Message text: First document using the number range number &1 not yet known
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The SAP error message SIAO_DEL107 indicates that the system is unable to find the first document using the specified number range. This typically occurs when the number range has not been properly defined or initialized in the system.
Cause: Number Range Not Defined: The number range for the document type you are trying to use has not been defined in the system. Number Range Not Initialized: The number range exists, but it has not been initialized, meaning that no documents have been created using that number range yet. Incorrect Configuration: There may be a configuration issue where the document type is not correctly linked to the number range. Authorization Issues: Sometimes, the user may not have the necessary authorizations to access or create documents in that number range.
Solution: Check Number Range Configuration: Go to transaction code SNRO (Number Range Objects). Find the relevant number range object associated with the document type. Ensure that the number range is defined and
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