Message type: E = Error
Message class:  FINS_FI_MASS_DATA - Mass Data Handling 
Message number: 404
Message text: Mass data activity &1 is still used in tables; For example: &2
You cannot delete mass data activity &v1& because it is still in use.
For example, table &v2& (&v3&) in client &v4& contains data records for
this activity.
The system issues an error message and will not allow you to continue with this transaction until the error is resolved.
Delete only unused mass data activities that have never been transported
for productive use. Mass data activities, which were used in previous
releases must remain in the system.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message FINS_FI_MASS_DATA404 indicates that a mass data activity (such as a mass change or deletion of financial data) cannot be completed because the data is still being referenced in certain tables. This typically occurs when you attempt to delete or modify data that is still linked to other records in the system.
Cause: The error is caused by the presence of dependencies or references in the database tables that prevent the mass data activity from being executed. For example, if you are trying to delete a financial document or master data, and there are still entries in related tables (like line items, transaction records, etc.) that reference the data you are trying to delete, the system will raise this error.
Solution: To resolve this error, you can follow these steps: Identify Dependencies: Check the specific tables mentioned in the error message (e.g., &2) to identify what data is still referencing the mass
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