Message type: E = Error
Message class:  CNV_CDOP_CA - CDOP Clearing Analysis 
Message number: 131
Message text: Enter at least one system with role A
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.
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The SAP error message CNV_CDOP_CA131 typically occurs in the context of the SAP Conversion and Migration tools, particularly when dealing with the SAP S/4HANA migration or data conversion processes. This error indicates that the system requires at least one system to be defined with the role "A" (which usually stands for "Application" or "Source System") in the configuration.
Cause: The error arises when: No source system has been defined with the required role "A" in the configuration settings. The system configuration is incomplete or incorrect, preventing the migration or conversion process from proceeding.
Solution: To resolve this error, you can follow these steps: Access the Configuration: Go to the relevant transaction in SAP where you can configure the system roles (often this is done in the transaction code CNV_MBT or similar). Define a Source System: Ensure that you have at least one system defined with the role "A". This typically involves: Navigating to the section where you can manage system roles. Adding
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