Just want to let you know that we removed the AddAccount operation from the MSDN documentation. The AddAccount operation is meant for internal use only. Calling AddAccount is not supported. Instead of calling AddAccount to add multiple accounts to a customer, you should call the SignupCustomer operation for each account that you need to add. Sorry for any inconvenience that this may cause.
If AddAccount is something that you’d like to use, please let us know the scenario in which you’d use it.