The major problem was use of Shared SSL or Lack of Dedicated SSL. She was using shared provided (Free one) by 3DCart.
Because if you use shared SSL, all your secure pages will be hosted on subdomain.3dcartstores.com.
And as it is not your primary domain, you need cross-domain tracking to keep up the original traffic source between your domain and subdomain of 3dcartstores. Otherwise you will have self-referral issues and Google Analytics will report that all the sales are coming from yourdomain.com/referral.
You won’t be able to track the performance of your Adwords or Facebook Ad campaigns, Email Marketing and ultimately ROI calculation will be really tough.
Also, I couldn’t find any simple cross-domain method for 3DCart. It’s really bad because you’ve to pay for an SSL certificate.
And it should work. Now, you can use Google Analytics to track ROI on all your marketing campaigns and channels.
Do you need any help with Analytics for your 3DCart store? Do you want to increase the revenue of your store? Hire me and let’s get started.