Message type: E = Error
Message class:  CNV_20211_CHECK - Messages for check functions (company conversion) 
Message number: 090
Message text: Participating companies
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The SAP error message CNV_20211_CHECK090 typically relates to issues encountered during the data migration process, particularly in the context of SAP S/4HANA migrations or conversions. This error is part of the SAP Conversion and Migration tools, which are used to facilitate the transition from older SAP systems to newer versions or to S/4HANA.
Cause: The error message CNV_20211_CHECK090 indicates that there is a problem with the participating companies in the migration process. This could be due to several reasons, such as: Missing or Inconsistent Data: The participating companies may not be properly defined in the system, or there may be inconsistencies in the data related to these companies.
Configuration Issues: There may be configuration settings that are not aligned with the requirements for the migration. Authorization Issues: The user executing the migration may not have the necessary authorizations to access or modify the data related to the participating companies. Data Model Changes: Changes in the data
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