An “unknown application error occurred” can happen when you try to process a payment with the First Data Connect payment gateway.
The main reason for this error is that you have used the test First Data Connect account details while trying to process a live payment. Kindly ensure that you have followed our setup guide using your test First Data Connect details first and then process a few test orders in test mode. To process your payments in test mode, please do refer to this link.
To know which mode your plugin is on, navigate from your WooCommerce > Settings > Payments > AG First Data Connect Checkout > Manage > Store Status. If you see the store status as “Test Environment,” your store is on test mode.
Once you have processed a few test orders in test mode, switch to live mode by changing the store status to Live Store.
You can check out the steps to process payments in live mode, as seen in this article.
What if there is an error?
That’s a bit unfortunate, but all problems in this world can eventually be fixed. Please do take a look at our Troubleshooting Guide, and hopefully, this would resolve the issue for you, or better yet, you could also contact our support, and one of our friendly support team members will sort out these issues for you.