The solution to this problem is to delete a certain trigger in the Harvest database that is left-over from the previous version of Harvest and is obsolete.
In order to locate the trigger to be deleted, login to SQL Server Management Studio, navigate to the Harvest database, expand the list of tables, and locate the dbo.HARFORMATTACHMENT table. Click the “+” to expand the details of the HARFORMATTACHMENT table, and expand the “Triggers” folder to find a trigger named HARUSDDEPLOYINFO_ATTID_TRIGGER. Right click on the name of the trigger and select “Delete”.
On the “Delete Object” dialog click “OK” to confirm.
Once the trigger has been deleted, you can stop and restart the SCM Broker. After that you should be able to delete the package without any further trouble.