On this site: http://www.kantoorstoel.nl/ I would only like to have the contact pages and the checkout area to work with SSL. For the contact pages, this was no problem using the plugin SSL redirect from Yireo. See for instance: https://www.kantoorstoel.nl/contact
I could not get this to work in the cart area however.
Then I read on other topics that OPC has the feature and that you simply have to check this option: "Use SSL everywhere possible on checkout"
Howver, this does not work for me. Any suggestions why not?