I was going to open a topic about this, but since you beat me to it, I’ll reply here!
Also checked the logs (WPEngine) and figured out there’s something wrong with the Previous and Next Post in Same Taxonomy plugin. Switched that off (with another external plugin that was causing trouble) and I didn’t have any error logs anymore.
Maybe Swift Ideas could consider taking up something else instead of this plugin to get the job done. This recurred a lot of times in the log:
[Wed Aug 14 13:54:06 2013] [error] [client 80.101.235.46] WordPress databasefout You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ‘) WHERE p.post_date < ‘2013-07-13 07:49:07’ AND p.post_type = ‘product’ AND p.po’ at line 1 bij query SELECT p.* FROM wp_posts AS p INNER JOIN wp_term_relationships AS tr ON p.ID = tr.object_id INNER JOIN wp_term_taxonomy tt ON tr.term_taxonomy_id = tt.term_taxonomy_id AND tt.taxonomy = ‘product_cat’ AND tt.term_id IN () WHERE p.post_date < ‘2013-07-13 07:49:07’ AND p.post_type = ‘product’ AND p.post_status = ‘publish’ AND tt.taxonomy = ‘product_cat’ ORDER BY p.post_date DESC LIMIT 1 /* From [eenliefde.nl/product/testproduct/] in [/nas/wp/www/cluster-1539/robthijs/bestanden/module/previous-and-next-post-in-same-taxonomy/previous-and-next-post-in-same-taxonomy.php:110] */ gemaakt door require(‘wp-blog-header.php’), require_once(‘wp-includes/template-loader.php’), include(‘/void/neighborhood/single-product.php’), woocommerce_get_template_part, load_template, require(‘/void/neighborhood/woocommerce/content-single-product.php’), be_previous_post_link, be_adjacent_post_link, be_get_adjacent_post, referer: http://eenliefde.nl/shop/
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