Customer information showing up after checkout

I just received a message from a customer who was trying to purchase an ebook. When she went to the sign in page, someone else's information was already in the form. She erased the information and put hers in, but had her friend go look on the friend's computer. Now, the friend saw her personal information. I just went to my site and added an ebook to the shopping cart, went to check out, and the form was blank. I used both Safari and Firefox as a browser. Neither brought up a completed form.

I am running 1.3.8. It's an upgrade from 1.3.5 to 1.3.6. I don't have any modifications other than the template from the basic Zen Cart template.

I have contacted my host, Pima Host, to see if it could be on their end.

My site is: http://www.freyasbower.com/. There are a number of free reads you can add to the cart if you want to test this.

Thanks,

Marci

Did the customer follow a link to your site from a URL that contained a session ID?

If there is a link out there somewhere to your site, and that link has a Session ID number tagged onto it, it tells your shop to pick up data relevant to that ID.

This could be the problem... or something else, but I doubt your host set up has anything to do with it.

There could be mis-matched data in the database too - again relating to stored session ID's.