Message type: E = Error
Message class:  FKK_ID_XX_ODN - ODN message 
Message number: 066
Message text: Impossible to change digital signature setting: numbering already started
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The SAP error message FKK_ID_XX_ODN066 indicates that there is an issue with changing the digital signature settings in the context of a document or transaction where numbering has already started. This typically occurs in the context of contract management, billing, or other financial documents where digital signatures are used for validation and approval.
Cause: The error arises when you attempt to change the digital signature settings after the numbering for the document has already begun. In SAP, once a document is created and assigned a number, certain settings related to that document become locked to maintain data integrity and consistency. Changing the digital signature settings at this point can lead to inconsistencies or conflicts in the document's lifecycle.
Solution: To resolve this error, consider the following steps: Check Document Status: Verify the status of the document you are trying to modify. If the document has already been created and numbered, you may not be able
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