Message type: E = Error
Message class:  CNV_LTHCM_S_10 - LT HCM: Message Class for Data Selection 
Message number: 218
Message text: Specify a customer selection type
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The SAP error message CNV_LTHCM_S_10218 indicates that a customer selection type must be specified in the context of a data migration or conversion process, particularly related to the SAP Landscape Transformation (SLT) or similar tools used for data migration.
Cause: This error typically occurs when: A required parameter for customer selection is missing in the configuration or execution of a migration program. The user has not defined or selected a specific customer selection type, which is necessary for the process to proceed. There may be a misconfiguration in the migration settings or a missing entry in the selection criteria.
Solution: To resolve this error, you can take the following steps: Check Configuration: Go to the relevant transaction or program where the error occurred. Ensure that you have specified a customer selection type. This could be a specific customer group, individual customers, or other criteria depending on the context of the migration. Review Documentation: Consult the documentation for the specific migration tool or
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