Upgraded to 1.5, having issues restoring 1.4.9.0, even after clean reinstall

[!sense]

Hi All

 

I installed 1.3.x.x,upgraded to 1.4.9.0 and had everything working flawlessly. Then 1.5 came out and I decided to upgrade with the 1-click module. Everything was not working as expected and I did not like the look, so i decided to roll back using the built-in functionality of the module.

 

At this point a lot of things were broken, but having made my own backups I was not concerned, deleted everything and restored the database as well as the files. After this I kept getting "Link to database could not be established". I checked the forums, confirmed that my password, prefix, username and database name were correct, but kept getting the error.

 

I deleted everything again, downloaded 1.4.9.0 and did a clean install on the server, and after this restored my database and files (img, mails, modules, download). Since my config was still the same (server name, database name, user name and password) I did not mess with config.inc.php.

 

Everything seems to work fine except the following:

1. When I click on "new products" in the front office I get:
   
   
2. When I click on the shopping cart or checkout, I get the same thing.
   

Any ideas? I have a full working backup as far as I can tell, but the other bits of prestashop that I'm not overwriting such as the modules and shopping cart is giving me issues?

[!sense]

Ok, I have downloaded and installed WAMP with versions as close as possible to my production server. I have restored both the database and the files onto this server, and I get exactly the same thing I got on the production server - Link to database cannot be established.

 

I will now see if I can fix this issue, instead of trying to salvage the current situation which was:

 

Do a clean PS 1.4.9.0 install

restore DB on top of that

restore img, mails, downloads, and custom modules.

 

The old shop worked perfectly, any newer bits seem to introduce their own and more exotic problems.

[!sense]

Despite the fact that I could swear I had all the details about the database authentication right, I once more proved that the problem lies with the user 99% of the time. I had mistyped the password for the database, causing the "Link to database cannot be established" error. I have corrected this and my restored version works the same as the newly installed 1.4.9.0 - i.e. the products display correctly and can be added to the cart, but when you try to view the contents of the cart, I still get the same error "Category does not exist" . I have also found quite a few of these errors on websites running online. This leaves me in the same position.

 

I now have exactly the same error whether I install 1.4.9.0 from scratch and restore my data to the new install, or whether I restore the whole website (database + files) to the server. I had MySQL check all the tbales and they are all fine according to MySQL. The only changes made by myself from the new install which one would assume to be working is really the img directory. The fact that the product display correctly in the front office and can be added to the cart leads me to believe the database and images cannot be the problem.

 

The question remains : Why would the cart give an error when checking out or when trying to display the contents?