Message type: E = Error
Message class:  CNV_20200_CHECK - Messages for check functions (company code merge) 
Message number: 253
Message text: Source value missing for (CoCd &1, house bank &2, new Acct ID &3)
Source value missing for (company code &V1&, house bank &V2&, new house
bank account ID &V3&)
Error
Provide a suitable mapping for house bank account ID's.
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 CNV_20200_CHECK253 indicates that there is a missing source value for a specific combination of Company Code (CoCd), House Bank, and New Account ID during a data migration or conversion process. This error typically arises in the context of the SAP S/4HANA migration or during the use of the SAP Conversion Tools.
Cause: The error is caused by the following reasons: Missing Data: The source data for the specified Company Code, House Bank, and New Account ID is not available in the migration data set. Incorrect Mapping: There may be an issue with the mapping of the source data to the target data structure, leading to the absence of expected values.
Configuration Issues: The configuration settings for the house bank or account ID may not be correctly set up in the system.
Solution: To resolve this error, you can take the following steps: Check Source Data: Verify that the source data for the specified Company Code,
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CNV_20200_CHECK252 Source Acct ID (CoCd &1, house bank &2, Acct ID &3) with missing target
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CNV_20200_CHECK254 Source house bank acc (CoCd &1, house bank &2, Acct ID &3) does not exist
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