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Customization
Troubleshooting
- Embedded checkouts in WooCommerce
- Checkout blocks in WooCommerce
- Error codes
- Compatible plugins and themes
- Known compatibility issues
- Files to exclude from optimization
- Shipping Methods in iframe
- FAQ
- Optimizing your checkout when using an Iframe-based checkout
- Callbacks
- Troubleshooting the checkout flow
- Troubleshooting the Pay for order/Hosted Payment Page flow
- Troubleshooting WooCommerce Subscriptions and KCO
- Kustom Developer logs
- Pending payment orders and held stock
Additional related plugins
Error codes
As Klarna Checkout transitions to Kustom Checkout, please note that parts of this documentation are still being updated. You may come across references to Klarna, outdated screenshots, or broken links.
We’re working continuously to revise all content, and we appreciate your patience during this process.
Common error codes from Klarna:
- 400 – Bad Value: purchase_currency
Your account at Kustom doesn’t seem to be configured for the currency used in your store. What currency did you select when you signed up with Kustom? If you need support, you should contact Kustom via their Knowledge Base or support@kustom.co. - 400 – Bad value: push
Your domain does not have a valid SSL Certificate. As of summer 2023 Kustom demands HTTPS. - 401 – Unauthorized
If you receive this error message it usually means that you are using your credentials for the wrong plugin. It could also mean that the username and/or password is incorrect, try copying & pasting instead of typing in directly and double check for whitespace. If you need support, you should contact Kustom via their Knowledge Base or support@kustom.co. - 403 – Forbidden
Make sure you are using an up to date version of KCO (minimum 2.12.3 and above). Earlier versions are blocked for usage from Kustom’s side. - 403 – Invalid_Operations
(403 error code means the Kustom credentials authenticate successfully (so Kustom API credentials/username & password are correct) but you haven’t selected the Kustom products to enable these credentials to work yet. You should be able to select products in the Kustom Merchant Portal, but if you need assistance, you should contact Kustom via their Knowledge Base or support@kustom.co. - 403 – Merchant_Inactive
This means that your Kustom credentials are NOT activated. If you need support, you should contact Kustom via their Knowledge Base or support@kustom.co. - 403 – PAYMENT_METHOD_FAILED
Check the reason. This usually happens when Kustom rejects a purchase. - 404 – Not found
Where credentials were changed during the order. Please make sure to start a new browser session after changing credentials. If you need support, you should contact Kustom via their Knowledge Base or support@kustom.co. - 405 – Method not allowed
Merchants are encountering issues when their Kustom credentials are a valid username & password, but aren’t correctly configured for the market they are using them for. If you need support, you should contact Kustom via their Knowledge Base or support@kustom.co.
Common error codes from our plugin:
- Kustom Checkout error (Failed to load Kustom Checkout template file.)
This means that there is another plugin or theme that overrides and makes our template file not to load correctly in the checkout.
This error message can also be shown when your WooCommerce Checkout page is missing the[woocommerce_checkout]
shortcode.