Message type: E = Error
Message class:  CNV_20200_CHECK - Messages for check functions (company code merge) 
Message number: 165
Message text: G/L account &1 assigned to company code &2, House bank &3, Account ID &4
G/L account &V1& is assigned to several House bank account IDs.
One of these house bank account IDs is:
Company code: &V2&
House bank ID: &V3&
House bank account ID: &V4&
Warning, with action required
This leads to a merge of G/L accounts, which belong to different bank
accounts before the merge. Check whether you want to merge the G/L
accounts nevertheless.  If you do not want to merge the G/L accounts,
you have to create a new G/L account, transfer the balance and adapt
your Customizing settings before the merge.
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_CHECK165 typically indicates an issue related to the configuration of a General Ledger (G/L) account in relation to a specific company code, house bank, and account ID. This error often arises during data migration or conversion processes, particularly when using SAP's Migration Cockpit or during the execution of specific conversion programs.
Cause: The error message CNV_20200_CHECK165 can be caused by several factors, including: Incorrect Configuration: The G/L account may not be properly configured for the specified company code or house bank. Missing Assignments: The G/L account might not be assigned to the house bank or the account ID in the system. Data Inconsistencies: There may be inconsistencies in the data being migrated, such as incorrect mappings or missing entries. Authorization Issues: The user executing the migration may not have the necessary authorizations to access or modify the specified G/L account or house bank.
Solution: To resolve the error, you can take the following steps: Check
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