Hello,
So table ca_class_def is ok.
Another things to check :
1- Check if following SQL query returns this row :
select * from ca_class_hierarchy where child_class_id=5478
If this line is not present in database then there is a problem with Software Content Download job.
2- Check if DSM Explorer used is at least version R14.0 (R14.0, SP1 or SP2).
Otherwise upgrade it to R14.0, R14 SP1 or R14 SP2
On DSM Explorer, the date of file CA\DSM\Agent\OSConfig.xml should be at least 25th of March 2016 and the size >= 75 Kb
Regards,
Jean-Yves