How To Fix CNV_20100166 - Alternative account (SKB1-ALTKT) is already filled in company code &1

CNV_20100166 - Overview

• Message type: E = Error

• Message class: CNV_20100 - Messageclass for chart of account conversion

• Message number: 166

• Message text: Alternative account (SKB1-ALTKT) is already filled in company code &1

What causes this issue?

According to the mapping table maintenance for company code &V1&, you
want to store the previous account numbers in the alternative account
number field (SKB1-ALTKT).

System Response

The system found that this field already contains data for company code
&V1&. During the conversion, this data would be overwritten.

How to fix this error?

Check if the existing data can be overwritten.
If this is <ZH>not</> the case, go to the mapping table maintenance and
remove the <ZK>Altkt</> indicator .
If the existing data can be overwritten this message can be ignored.

Error message extract from SAP system. Copyright SAP SE.

CNV_20100166 - Details

• The SAP error message CNV_20100166 indicates that there is an issue with the alternative account (field SKB1-ALTKT) in the company code specified. This error typically arises during data migration or conversion processes, particularly when using the SAP S/4HANA Migration Cockpit or similar tools.
  
  Cause:
  The error occurs when the alternative account field (ALTKT) is already populated for the specified company code. This can happen if:
  
  The alternative account is being set for a G/L account that already has an alternative account assigned.
  There is an attempt to assign a new alternative account to a G/L account that already has one, violating the uniqueness constraint for that field.
  
  
  Solution:
  To resolve this error, you can take the following steps:
  
  
  Check Existing Data:
  
  Use transaction code SE16N or SE11 to check the SKB1 table (G/L account master data) for the specified company code and see if the ALTKT field is already filled.
  Identify the G/L accounts that have an alternative account