Thanks for your response Nicolas, by adding https:// this has indeed sorted the url issue to the SSL. However this has now lead to a new problem - now when I press the 'Proceed to Checkout' button, it simply empties the shopping cart, and doesn't go to the checkout page at all. If I press to go back to the home page of my site, the products in the cart then reappear, but if you press proceed to checkout, the same problem, it empties the cart.
Can you take a look at it for me, the link to my site is:
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If you add one of the products from the front page, so you will see what I'm saying.
Thanks as ever for your help,
Keith