Message type: E = Error
Message class:  FKKBIX - Conv.Inv.: Billing (Invoice Preprocessing) 
Message number: 195
Message text: Index is provided by SAP and cannot be changed
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The SAP error message FKKBIX195 indicates that an index is provided by SAP and cannot be changed. This typically occurs in the context of financial accounting, particularly when dealing with the configuration of indexes for the document index in the SAP system.
Cause: The error arises when there is an attempt to modify or delete an SAP-provided index that is essential for the system's functionality. SAP provides certain indexes to optimize performance and ensure data integrity, and these indexes are not meant to be altered by users.
Solution: Do Not Modify SAP Indexes: The primary solution is to refrain from attempting to change or delete the SAP-provided index. Instead, you should use the indexes as they are configured by SAP. Check Custom Indexes: If you need to create custom indexes for your specific requirements, ensure that you are not trying to modify the standard SAP indexes. You can create new indexes that do not interfere
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