The Klarna Checkout for WooCommerce plugin can be downloaded from here.
An SSL certificate is required for the Klarna Checkout (KCO) module.
Once installed and activated, the plugin's settings can be found in WooCommerce ⇒ Settings ⇒ Payments ⇒ Klarna Checkout.
Enable Klarna Checkout by checking the Enable Klarna Checkout checkbox.
Test mode allows you to test your integration to ensure it is working properly before taking real orders. You can sign up for test credentials here.
Log debug messages will log plugin debug messages in WooCommerce ⇒ Status ⇒ Logs.
You can generate your Klarna API credentials in the Settings app of the Klarna Merchant Portal. These will consist of a username and password.
Once generated, you will enter these credentials in the Production Klarna API username and Production Klarna API password fields for the appropriate country(ies).
If you generated test credentials following the above link, you will enter these in the Test Klarna API username and Test Klarna API password fields.
Make sure you click Save changes at the bottom of the page.
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