Message type: E = Error
Message class:  CNV_LTHCM_G_10 - LT HCM: General Message Class 
Message number: 012
Message text: Communication failure when calling function module '&1', destination &2:
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The SAP error message CNV_LTHCM_G_10012 indicates a communication failure when calling a function module. This error typically arises in the context of data migration or conversion processes, particularly when using the SAP Landscape Transformation (SLT) or other data migration tools.
Cause: Network Issues: There may be network connectivity problems between the SAP system and the destination system. Incorrect Destination Configuration: The destination system may not be correctly configured in the SAP system (e.g., RFC destination settings). Authorization Issues: The user or service account may not have the necessary authorizations to access the function module in the destination system. Function Module Not Available: The specified function module may not exist in the destination system or may not be activated. Timeouts: The call to the function module may be timing out due to long processing times or heavy load on the destination system.
Solution: Check Network Connectivity: Ensure that there is proper network connectivity between the SAP systems. You can
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