Facebook like buttons on your product pages are a nice touch to your social media marketing endeavors. However, it's quite discerning when someone shares your product page and posts a button or other stupid image instead of the product image. Several requests lead me to try to solve this... and I believe I have, with the following "tweak" for your Zen Cart.

    First make sure you are using the Facebook Like button on your product pages. Next you are going to add a simple edit to your html_header.php
    So navigate to includes/templates/your_template/common/html_header.php and back it up!
    If you lack a html_header.php in that loaction got to includes/templates/template_default/common/html_header.php download it and upload it to includes/templates/your_template/common/
    Now, at some logical location we will add one line of markup using the Facebook Open Graph protocol for the meta property="og:image"
    Generally speaking we want to add this without breaking up a php process. I suggest you add it right after <?php } //endif FAVICON ?>

You will be adding the following line:

<meta property="og:image" content="<?php echo zen_image(DIR_WS_IMAGES . $product_info->fields['products_image'], $product_info->fields['products_name'], IMAGE_PRODUCT_LISTING_WIDTH, IMAGE_PRODUCT_LISTING_HEIGHT) ?>"/>

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