Authorize.net - Invalid Notification

Hi,

The "Invalid notification" error means that the hash validation between Authorize.net and HikaShop failed. The plugin compares a hash calculated from the notification data with the hash sent by Authorize.net to verify authenticity.

Since you mentioned that most transactions work fine and this is intermittent, it is likely related to special characters in the customer's name or address. The SHA-512 signature hash includes customer data fields (name, address, city, state, zip, etc.) and if any character is encoded differently between what Authorize.net sends and what PHP receives, the hash will not match.

Could you check: do you have a Signature Key configured in the plugin settings? This is different from the MD5 Hash field. Authorize.net deprecated the MD5 method back in 2019, so you should be using the Signature Key (SHA-512) instead. You can find/generate your Signature Key in your Authorize.net merchant account under Account > Settings > Security Settings > General Security Settings > API Credentials & Keys.

Also, could you check if the affected transactions have something in common? For example, customers with accented characters in their names, special characters in their addresses, or non-US addresses? That would help confirm whether this is a character encoding issue in the hash calculation.

If you have debug mode enabled in the payment method settings, you should also be able to get more information about the problem in the "Payment log file" under the HikaShop configuration page. The details there will help us pinpoint the exact cause.

Hi,

You don't need to clear out the MD5 Hash box, but you can if you want. It won't change anything.
Report to us once you get the issue again with the debug turned on so that we can check the payment log file.