Fatal error on last step of ordering - on some, not all, old customers

[gameplay]

I have upgraded to 1.4.17 - BIG MISTAKE - and (apart loosing most of the photos) and a lot of bugs with prices display etc., the most upseting one is that some of my old customers, not all of them, get "fatal error" on pressing the "I confirm the order" button on the last step of ordering.
Does anyone has this problem also?
Until now, all I could do was to tell them to open another account, but this is embarrasing.

[Jupiterr]

We need more details to see whats happening. Try to show the errors (http://www.prestashop.com/forums/viewthread/67298/development/solved_cant_get_errors_to_show/) or what that Fatal Error says.

Anyway, before upgrade, you have should tested with a copy of your installation. You could copy your images table to recover your images. Check the clients table and compare the ones who gave errors with the new ones.

Good luck.

[gameplay]

It just says "Fatal error" - nothing else.
I have no developement experience, I am just a begginer user, and I was extremely happy with the version 1.3, did not had any problem AT ALL with it, and now it seems that the problems keep piling up.
It was not specified in the installation guide that I sould copy the images table, just to copy my images.
I will try to look into the clients table and try to see if I can figure out something.
Thanks for the tip, I will be back.

[Jupiterr]

Maybe you can solve all the problems easily, or maybe not. Anyway, in the future, before upgrading anything copy the database and the files. The MYSQL GUI Tools are great and easy to use.

With MySQL Gui Tools (MySQL Query Browser) you can check if the image field of the products is ok. Maybe that field is wrong, maybe there is nothing on that field.

Regards.

[gameplay]

I checked the customer table and found nothing suspect with the clients that have thid difficulty.

However, I foud out that some of the tables have "PS_" in front of the name, and some dont. I remember that all the tables should have "PS_" as a prefix, ad least they used to in the 1.3 version. Even more, there are sometimes 2 tables with the same name, one that has the prefix "ps_" and one that does not. For instance I have the table "zone" and another one "ps_zone". Can somebody please tell me if this is normal?

I am beginning to be extremely worried, since I found more errors, like customers telling me that they have placed the order, and I cant find the order, it was not validated by the sistem.