Customers seeing other customer info

the site is

www.cottagecooks.co.uk

The first problem we have on the site is that customers were reporting to see one anothers cart contents in the check out process. Then we established that the zenid was being picked up in the who's online (should this be?)

After that we changed the config > sessions to force cookies some customers can not even log in or check out

is this a bug in zencart or something else

Please Help

Thanks in advance:ohmy:

What version of Zen Cart are you running?

Are you able to successfully run your site with this enabled in the Configuration ... Sessions settings:

Recreate Session
Recreate the session to generate a new session ID when the customer logs on or creates an account (PHP >=4.1 needed).

You need to test from add to cart to create account to checkout to logout to login etc.

open phpmyadmin,
make sure that no one is in your cart,
empty the sessions table,
then turn on re-create sessions