Message type: E = Error
Message class:  CNV_IUUC_REPL_ADV_SE - MEssage class for package CNV_IUUC_REPL_ADV_SETTINGS 
Message number: 120
Message text: Switch to change mode
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The SAP error message CNV_IUUC_REPL_ADV_SE120 typically occurs during the data migration process, particularly when using the SAP Landscape Transformation (SLT) replication or during the execution of the SAP S/4HANA migration cockpit. This error indicates that the system is not in the correct mode to perform the requested operation, specifically that it needs to switch to "change mode."
Cause: The error is generally caused by one of the following reasons: Incorrect Mode: The system is currently in a mode that does not allow for changes, such as display mode or a mode that is not suitable for the operation being attempted.
Configuration Issues: There may be configuration settings that prevent the system from switching to change mode. User Permissions: The user executing the operation may not have the necessary permissions to switch modes or perform the required actions.
Solution: To resolve the CNV_IUUC_REPL_ADV_SE120 error, you can take the following steps: Switch to Change Mode: Ensure that you are in the
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