Ive just discovered a new problem with my site.
Once ive added a product to the cart and then click the "back to shopping" button, it returns me to the page i was (All good here) BUT if i add a different product FROM THE SAME CATEGORY, as the previously added product, it seems to add another of the previous product rather than add the new second product.
eg,.. I now have two of the same product in my cart rather than 2 different products.
VERY ODD!
If however i add a product form a different category OR if i go back to shopping via clicking on the "home" tab, all works fine. ???

HELP! I seem to be getting a few abandoned carts with this problem.

The only change i have made recently is to change all my products form:
Qty box status 1 to 0 in all the products.

the site is:

www DOT blue55 DOT co DOT nz

And if you turn off the SEO/rewites that you are using?

What happens if you switch to the Classic Template?

Ajeh:

And if you turn off the SEO/rewites that you are using?

What happens if you switch to the Classic Template?

interesting, turned off the SEO Url and all worked fine. Is there a way to fix this as i really like the SEO URL?

I don't use the SEO ... the issue is the products_id on the URL ... you will notice that if you mouse over the buy now buttons from a listing that all of them have the same products_id on them so that is being used on the add to cart ...

Ajeh:

I don't use the SEO ... the issue is the products_id on the URL ... you will notice that if you mouse over the buy now buttons from a listing that all of them have the same products_id on them so that is being used on the add to cart ...

Thanks so much Ajeh...
Perhaps the solution would be to change the direction of the "back to shopping" button to a more universal location like the home page. Is there an option to change this?

I'd really look to fix the issues with your SEO/rewites as this could indicate other issues are lurking ...

Im afraid i wouldnt even know where to begin,
I see this guy has the same problem
http://www.zen-cart.com/forum/showthread.php?t=52865

heres the htaccess rewrite i have:

NOTE: Replace /shop/ with the relative web path of your catalog in the "Rewrite Base" line below:

Options +FollowSymLinks
RewriteEngine On
RewriteBase /

From Ultimate SEO URLs

RewriteRule ^(.)-p-(.).html$ index.php?main_page=product_info&products_id=$2&%{QUERY_STRING} [L]
RewriteRule ^(.)-c-(.).html$ index.php?main_page=index&cPath=$2&%{QUERY_STRING} [L]
RewriteRule ^(.)-m-([0-9]+).html$ index.php?main_page=index&manufacturers_id=$2&%{QUERY_STRING} [L]
RewriteRule ^(.)-pi-([0-9]+).html$ index.php?main_page=popup_image&pID=$2&%{QUERY_STRING} [L]
RewriteRule ^(.)-pr-([0-9]+).html$ index.php?main_page=product_reviews&products_id=$2&%{QUERY_STRING} [L]
RewriteRule ^(.)-pri-([0-9]+).html$ index.php?main_page=product_reviews_info&products_id=$2&%{QUERY_STRING} [L]
RewriteRule ^(.*)-ezp-([0-9]+).html$ index.php?main_page=page&id=$2&%{QUERY_STRING} [L]

For Open Operations Info Manager

RewriteRule ^(.*)-i-([0-9]+).html$ index.php?main_page=info_manager&pages_id=$2&%{QUERY_STRING} [L]

For dreamscape's News & Articles Manager

RewriteRule ^news/?$ index.php?main_page=news&%{QUERY_STRING} [L]
RewriteRule ^news/rss.xml$ index.php?main_page=news_rss&%{QUERY_STRING} [L]
RewriteRule ^news/archive/?$ index.php?main_page=news_archive&%{QUERY_STRING} [L]
RewriteRule ^news/([0-9]{4})-([0-9]{2})-([0-9]{2}).html$ index.php?main_page=news&date=$1-$2-$3&%{QUERY_STRING} [L]
RewriteRule ^news/archive/([0-9]{4})-([0-9]{2}).html$ index.php?main_page=news_archive&date=$1-$2&%{QUERY_STRING} [L]
RewriteRule ^news/(.)-a-([0-9]+)-comments.html$ index.php?main_page=news_comments&article_id=$2&%{QUERY_STRING} [L]
RewriteRule ^news/(.)-a-([0-9]+).html$ index.php?main_page=news_article&article_id=$2&%{QUERY_STRING} [L]

All other pages

Don't rewrite real files or directories

RewriteCond %{REQUEST_FILENAME} !-f [NC]
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*).html$ index.php?main_page=$1&%{QUERY_STRING} [L]