In order to communicate with Amazon's Product Advertising API, the PHP SOAP extension must be enabled on your server.
In case you're not sure if it's enabled or not, let's find out:
- Inside the plugin's admin area, click on the menu item “Support“
- At the bottom of the page you can find the section “Environment“.
Here you can find an info wether PHP SOAP is enabled or not
Right now the usage of this extension is required. The plugin cannot be used without.
All other requirements are listed here.