IF you have more than one oscommerce using one database you may encounter problems adding products to your articles in 'articles_xsell.php'

Solution: about line 200 change:
"$query = "[...] TABLE_PRODUCTS_DESCRIPTION . " pd, products_to_categories p2c where p2c.categories_id=[...] ";"

into:
"$query = "[...] TABLE_PRODUCTS_DESCRIPTION . " pd, " . TABLE_PRODUCTS_TO_CATEGORIES . " p2c where p2c.categories_id=[...] ";"

products_to_categories --into--> " . TABLE_PRODUCTS_TO_CATEGORIES . "

Although it looks similar it makes difference.
Thanks for great contribution.
File added: THIS TEXT ONLY

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