How can I take a transaction ID, and turn that transaction into a subscription from the API in PHP? In the back-end you just click the "Create ARB Subscription from Transaction" link in the upper right hand corner of transaction details box, and it links you to a page to create it. wondering how to do this via the API. Thanks for any help!
You don't. Unless you have a unique order info like the invoice# or purchase order# that you can reference back to the profileID/payment profile ID by using the http://developer.authorize.net/api/transaction_details/