Message type: E = Error
Message class:  CNVMBTRFC - Messages used in RFC Management and its objects 
Message number: 146
Message text: Change password of destination &1 in the definition tab
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The SAP error message CNVMBTRFC146 indicates that there is an issue with the password of a destination in the definition tab of a conversion or migration project. This typically occurs in the context of using the SAP Landscape Transformation (SLT) or other data migration tools where RFC (Remote Function Call) destinations are configured.
Cause: The error is caused by one of the following reasons: Expired Password: The password for the specified RFC destination has expired or has been changed in the target system without updating it in the source system. Incorrect Password: The password entered for the RFC destination is incorrect.
Configuration Issues: There may be issues with the configuration of the RFC destination itself, such as missing or incorrect parameters.
Solution: To resolve the error, follow these steps: Check RFC Destination: Go to transaction SM59 in the SAP GUI. Locate the RFC destination that is mentioned in the error message (denoted as &1). Check the connection settings and ensure that
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