SOLVED. (And working)
If your site points to an HTTP and HTTPS, you will get an error trying to add a product to your cart. Change to the following settings and all good.
Normal pages in OC aren't HTTPS enabled and will go to HTTP even if you were on HTTPS to begin with. To get your whole site to use HTTPS globaly, open: /system/library/url.php
Find this Code:
$url = $this->url;
change code to:
$url = $this->ssl;
I just altered my config.php files in the install & admin directory to edit the HTTPS settings and since then, I am now getting an error "Error undefined" when trying to add a product to the shopping cart. Have no problem with HTTP. Also lately Ive been getting emails from sitelock advising that I have malware on my server. Could this have happened when I didnt use SSL right away?
Any assistance would be greatly appreciated.