When cloning a job, I got an error saying "Invalid jobs cannot be cloned. Please create a new job." Why and what can I do?

This is most likely caused by changes in your database, making the job invalid due to missing fields or objects, as described in our article Actions to avoid while using TaroWorks. 

In some cases you might be able to undo the changes in your object/fields, but if that is not possible then you must create a new job from the beginning.