WPPizza – Authorize.net Gateway

SIM (Server Integration Method) OR – as of version 2.0 – AIM (Advanced Integration Method) implementation of the Authorize.net Gateway for Integration with WPPizza.


  • install by uploading the zip file in the normal wordpress manner from withing the plugin screen (add new->upload) and activate
  • go to wppizza->gateways and set options as required


  • you MUST (obviously) have an Authorize.net account with corresponding “API Login Id” and “Transaction Key”
  • the currency set in WPPizza->Order Settings MUST be enabled/accepted in your Authorize.net account
  • you MUST set your “Silent Post URL” (Settings->”Silent Post URL”) in your Authorize.net account
    (see screenshot here) – the exact url will be shown in your gatway settings
    This url must also be publicly accessible (i.e not password restricted)
  • make sure access to the “Silent Post URL” is not blocked by a firewall or other security mechanisms. please note: Authorize.net does not use a useragent. If you use a application firewall (for PCI purposes), you may need to disable any filters having to do with blocking requests from users with empty user agents.
  • you SHOULD set “Tax” (if you charge tax), “Freight” (if you offer delivery) and “Duty” (if you apply any surcharges)  to be visible in your Authorize.net account “View” column (Settings -> Payment Form -> Form Fields) (see screenshot here)
    Although it will work without these fields enabled , your customers might get confused as items will not show up on the payment page even though they are being charged for them.
  • AIM integration requires php 5.3+, SSL certificate, PCI compliance, cUrl and Simple XML
  • If you opt for the AIM integration it is MANDATORY to have your wppizza checkout page secured by an SSL certificate. Furthermore, authorize.net requires PCI compliance of your server. Please contact authorize.net if you have questions about detailed requirements regarding AIM implementation.

Important Setup/Update – for updates from versions prior 3.5

  • As of late June 2019, Authorize.net has stopped supporting MD5 hashes for SIM integrations
  • If using SIM you MUST now generate (“Authorize.net Account->Settings->Api Credentials & Keys : Signature Key”) and enter this 128 char signature key into relevant field in the plugin settings (“WPPizza->Gateways->Authorize.net”)


  • first of all, make sure the silent post url you have set in your authorize.net account is accessible. i.e go to that url (typically www.mydomain.com/wp-content/plugins/wppizza-gateway-authorize.net/ipn/ipn.php) in your browser. if it returns anything other than a blank page, for example an error page, this must be fixed
  • If you still experience any problems or have any questions, please enable logging in the plugin and send any logs you find in the logs/ directory of the plugin (i.e wp-content/plugins/wppizza-gateway-authorize.net/logs )to dev[at]wp-pizza.com with a description of the problem you are having