Message type: E = Error
Message class:  CNV_20211_CHECK - Messages for check functions (company conversion) 
Message number: 103
Message text: Company &1 uses FI-SL Ledger &2 with Activity &3: Posting Indicator &4
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The SAP error message CNV_20211_CHECK103 typically occurs during the migration or conversion process when using the SAP S/4HANA Migration Cockpit or similar tools. This error is related to the Financial Accounting (FI) module, specifically concerning the use of Special Ledgers (FI-SL) and the configuration of posting indicators.
Cause: The error message indicates that there is a configuration issue with the company code and the special ledger being used. Specifically, it points out that the posting indicator for the specified activity is not set correctly for the given company code and ledger. This can happen due to: Incorrect Configuration: The posting indicator for the activity in the special ledger is not defined or is incorrectly set. Missing Entries: There may be missing entries in the configuration tables for the special ledger. Inconsistent Data: The data being migrated may not align with the expected configuration in the target system.
Solution: To resolve this error, you can take the following
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