Topic: Can't add product to cart

Hello,

You need update theme to 3.0.0.1 v (http://themeforest.net/item/woopress-responsive-ecommerce-wordpress-theme/9751050, log in with your Envato account credentials and free download the latest version in Downloads section)
http://www.8theme.com/demo/docs/woopress/#!/installation_upgrade.
Don’t forget to create backup of your files and database before starting update process!
You need to enter your purchase code to activate our new theme version and skip Setup Wizard.
Also, update all required plugins https://www.8theme.com/download-plugins/.

Regards

Yes, we know about this, but you use 2.8 theme version and WC 3.1.1, very likely update of the theme will help you to solve the problem of add to cart. We didn’t find critical compatibility errors of our theme with WC, except outdated files. Or try to downgrade woocommerce version http://prntscr.com/fxn40y
Create backup of your files, database and theme options (Theme Options > Import/Export > Options > Export Options) to be able to restore the site to previous state if something goes wrong.

Regards