How To Fix CNV_DMC_SIN266 - Class &1 / &2 already exists

CNV_DMC_SIN266 - Overview

• Message type: E = Error

• Message class: CNV_DMC_SIN - Messages for s-innovations migration

• Message number: 266

• Message text: Class &1 / &2 already exists

Self-Explanatory Message

Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.

To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.

Unfortunately, there isn't any extra information in this error notice.

What else can you do?

First, use our AnswerBot below to get a possible cause and solution (requires a premium subscription).

Also, review the in-depth Common Questions & Answers listed below; you could discover a solution there or be able to connect with others who have faced similar challenges.

You can also try searching the SAP support portal (support.sap.com) but you need a special user ID to access it. It is possible that an SAP support note exists that provides additional details about the mistake or even steps for fixing it.

CNV_DMC_SIN266 - Details

• The SAP error message CNV_DMC_SIN266 typically indicates that there is an attempt to create or insert a record in a database table where a record with the same key already exists. This error is often encountered during data migration or conversion processes, particularly when using the SAP Data Migration Cockpit or similar tools.
  
  Cause:
  
  Duplicate Entries: The most common cause is that the data being imported or migrated contains duplicate entries for a unique key or primary key constraint in the target database table.
  Data Preparation Issues: The source data may not have been properly cleaned or deduplicated before the migration process.
  Incorrect Mapping: There may be an issue with how the source data is mapped to the target structure, leading to conflicts.
  Previous Migration Attempts: If a migration process was previously run and not completed successfully, it may have left behind records that are causing conflicts.
  
  
  Solution:
  
  Identify Duplicates: Review the source data to identify any