Hey there, I'm seeing this error with my Clickbank in-front set up: IPN seems to be received from unknown source, not from the paysystem Looking in the logs I can't see any real clues - so I'm stumped as to how to progress. I've got a couple of licences / installations - and this is the first time I've seen the error. Any pointers? Thanks Exception Am_Exception_Paysystem_TransactionSource Am_Paysystem_Transaction_Incoming->validate [ library/Am/Paysystem/Transaction/Abstract.php : 48 ] Am_Paysystem_Transaction_Abstract->process [ library/Am/Paysystem/Transaction/Incoming.php : 250 ] Am_Paysystem_Transaction_Incoming->process [ library/Am/Paysystem/Transaction/Incoming/Thanks.php : 14 ] Am_Paysystem_Transaction_Incoming_Thanks->process [ library/Am/Paysystem/Abstract.php : 493 ] Am_Paysystem_Abstract->thanksAction [ library/Am/Paysystem/Abstract.php : 441 ] Am_Paysystem_Abstract->directAction [ application/default/plugins/payment/clickbank.php : 129 ] Am_Paysystem_Clickbank->directAction [ application/default/controllers/DirectController.php : 28 ] DirectController->__call [ library/Am/Controller.php : 118 ] Am_Controller->dispatch [ library/Zend/Controller/Dispatcher/Standard.php : 308 ] Zend_Controller_Dispatcher_Standard->dispatch [ library/Zend/Controller/Front.php : 954 ] Zend_Controller_Front->dispatch [ library/Am/App.php : 1985 ] Am_App->run [ index.php : 92 ] <invoice-log-item type="incoming-request"> <url> <method>GET</method> <scheme>http</scheme> <base_url/> <path_info>/payment/c-b/thanks</path_info> <host>munged</host> <remote_addr>1.2.3.4</remote_addr> </url> <params> <param name="item">4</param> <param name="cbreceipt">2XNRE7TP</param> <param name="time">1425400372</param> <param name="cbpop">03841057</param> <param name="cbaffi">SEXEWORK</param> <param name="cname">MR TESTER</param> <param name="cemail">check@munged.null</param> <param name="ccountry">GB</param> <param name="czip">SW1A1AA</param> <param name="cbskin">9846</param> </params> </invoice-log-item>