Message type: E = Error
Message class:  CNV_20100 - Messageclass for chart of account conversion 
Message number: 254
Message text: 'Indicator: account managed in ext. syst.' of &1 differs from &2 in cc &3
Accounts &V1& and &V2& have different values for the indicator
<zk>'account managed in external system' (WMETH)</> in company code &V3&
.
These accounts are to be converted into a single new account called
&V4&.
This may lead to problems.
The conversion can take place anyway.
Check if you really want the merge to take place in this way. If not,
change the mapping table accordingly.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message CNV_20100254 typically occurs during data migration or conversion processes, particularly when using the SAP S/4HANA Migration Cockpit or similar tools. This error indicates a discrepancy between the account management settings in the source system and the target system for a specific account in a particular company code.
Cause: The error message "Indicator: account managed in ext. syst. of &1 differs from &2 in cc &3" suggests that: The account in question is set to be managed in an external system in one of the systems (either the source or the target). The settings for account management (e.g., whether the account is managed in an external system or not) differ between the two systems for the specified company code.
Solution: To resolve this error, you can take the following steps: Check Account Settings: Verify the account settings in both the source and target systems. You can do this by checking the account master data in
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