Message type: E = Error
Message class:  CNV_PE_IF_RT - PE: Interfaces Runtime generation 
Message number: 035
Message text: Exception handling source not exists TRULE: &1 parameter mapping ID: &2
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The SAP error message CNV_PE_IF_RT035 indicates that there is an issue with the exception handling in the context of a parameter mapping ID during a data conversion or migration process. This error typically arises in the context of SAP's data migration tools, such as the SAP S/4HANA Migration Cockpit or other data transfer processes.
Cause: The error message suggests that the system is trying to reference a source that does not exist for the specified parameter mapping ID. This can occur due to several reasons: Missing Configuration: The parameter mapping ID specified in the error does not have a corresponding source defined in the configuration. Incorrect Mapping: There may be an error in the mapping configuration where the source or target fields are not correctly defined. Data Migration Tool Issues: If you are using a specific data migration tool, there may be bugs or issues with the tool itself that lead to this error. Transport Issues:
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