Here is are the most common errors:
Invalid 4020: Information received from an Invalid IP address.
The Sage Pay system will only accept registration POSTs from servers whose IP Addresses have been registered with them. If they receive a POST from any other server, you will see this error message. You need to add the server IP.
Malformed 3034: The Vendor or VendorName value is required.
The Vendor field should contain the vendor name supplied by Sage Pay. It will only ever contain a maximum of 16 characters consisting of numbers and letters with no spaces or unusual characters.
Invalid 3140: TheDeliveryCountry value is invalid
On WooCommerce, make sure you have set up shipping methods; the shipping data is missing because there is no shipping option in WooCommerce.
You should also be aware that:
- The MySagePay system tells you what errors have occurred, i.e., looking like “Invalid 3140,” which you can look up in the integration guide.
- You’re best testing all of this in the “test” gateway first, but you must recreate all settings on the live and repeat testing.