Message type: E = Error
Message class:  FINS_FI_SIF - SAP S/4HANA Finance: Subsequent Implementation of Functions 
Message number: 301
Message text: Posting to ledger &1 before fiscal year &2 is not permitted
Ledger &V1& has been introduced for company code &V3& with the
activation fiscal year &V2&. Postings to this ledger before &V2& are not
permitted.
The system issues an error message and will not allow you to continue with this transaction until the error is resolved.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message FINS_FI_SIF301 indicates that there is an attempt to post a financial transaction to a ledger before the specified fiscal year is open. This is a common issue in financial accounting within SAP, and it typically arises when users try to post transactions to a period that is not yet available for posting.
Cause: The error occurs due to the following reasons: Closed Fiscal Year: The fiscal year you are trying to post to is closed or not yet open in the system. Ledger Configuration: The specific ledger you are trying to post to may have restrictions on posting to certain periods or years. Posting Period Settings: The posting period settings in the configuration may not allow postings to the specified fiscal year.
Solution: To resolve this error, you can take the following steps: Check Fiscal Year Status: Go to the transaction code OB52 (Change Posting Periods) to check the status of the fiscal year and
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FINS_FI_SIF300 *------  Message Area 300 - 400 used for checks in legacy coding --------
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