Message type: E = Error
Message class:  CNV10400 - Messages for package 10400 (characteristics) 
Message number: 301
Message text: No CNVDOMS entries for package &1 found
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The SAP error message CNV10400301 indicates that there are no CNVDOMS (Conversion Domain) entries found for a specific package in the system. This error typically arises during data migration or conversion processes, particularly when using SAP's data migration tools.
Cause: Missing CNVDOMS Entries: The primary cause of this error is that the system is unable to find the necessary conversion domain entries for the specified package. This could be due to: The package not being properly defined or configured in the system. The relevant entries not being created or activated in the CNV (Conversion) tables. The package being incorrectly referenced or not existing in the system. Incorrect Configuration: There may be issues with the configuration of the data migration tools or the specific package being used. Transport Issues: If the package was transported from another system, there may have been issues during the transport process that resulted in missing entries.
Solution: Check CNVDOMS Entries: Use transaction codes like SE11
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