To change the value of createdOn value in MS dynamics CRM with c# :
you must use the early bound to change the value of createdOn
I want to creat a phonecall entity with specific value of createdOn field:
PhoneCall phonecall = new phonecall();
phonecall.Subject = "Communication";
phonecall["createdon"]=new date ("19/07/2016");
phonecall["overriddencreatedon"] = new date("19/07/2016);
You must change the overriddencreatedon to change the createdOn.
I used MS dynamics CRM 2016.