SSL problem with PHP sessions

#1

Hi. At risk of sounding like a total idiot here but here goes…
I have a small e-commerce site with was running fine until I got an SSL certificate installed. Then the problems started. Now my shopping cart will not store the information and empties itself every time a customer navigates to a different page (either to browse other products or to go to the checkout) having raised a support ticket with Foreground who make the rapidcart software I have been using, they said

RapidCart Pro relies on PHP sessions to temporary store cart content. If cart is empty when you change page or simply refresh, it means that PHP sessions are not correctly configured.

Please report the problem to your hosting provider.

I opened a ticket with my host 123reg who said they had checked the code in the .htaccess file and the site was loading fine at their end. This did not solve my problem. I’m in a bit of a tennis match between the two companies as both say it’s a problem with the other.
I’m not going to pretend to understand what half of this means as I’ve built my site through rapidweaver because it’s supposed to be for people who don’t know coding. It’s great till something goes wrong…then I have no clue how to fix it.
If it’s something I need to get my hosting service to address,does anyone on here know what it is I need to ask them to do. Likewise if it’s a problem at my end,does anyone on here have experience of what could have changed since I went to the HTTPS version of my site?

Sorry if this is a stupid question but I’m tearing my hair out.
Jim

#2

This is not a dumb question, it’s something that can happen. Turning on session support automatically at the site level is done in the php.ini file which is on the web server, so your hosting provider will be the one to modify this if needed. Not sure if this helps, I am not familiar with RapidCart.