Reply to email

To set the sending email to the store owner's address on the Contact Us page, run SQL like

INSERT INTO configuration (configuration_title, configuration_key, configuration_value, configuration_description, configuration_group_id, sort_order, date_added) VALUES ('E-Mail From', 'EMAIL_FROM', 'root@localhost', 'All e-mails will be sent from this address', 12, 6, NOW());

Change the root@localhost as appropriate for your server. E.g. to the same setting as STORE_OWNER_EMAIL_ADDRESS.

When you do this, it will automatically move the sending email to the Reply-to header. You can see the code at https://github.com/CE-PhoenixCart/PhoenixCart/blob/1.0.8.5/includes/system/versioned/1.0.8.5/email.php#L389..L391 (the line numbers may change in the future).