When using WooCommerce the add-to-cart form will send a long data string, which represents the customized product thumbnail, to the cart.

Problem: PHP post_max_size is to low

You need to increase the post_max_size variable. This article explains how to increase the value. Our support can not assist to help with that, therefore you need to contact your provider.

Problem: Your server is blocking the request

Because a long data string is sent to your server, some server might block the request. Therefore check out your error log file and check for any error. Contact your provider for any help, we can not assist with technical support for server configuration.

If you are not able to solve the issue, the only possibility is to turn off the "Customization Product Thumbnail" option. Therefore go to FPD settings > WooCommerce > Cart/Order.