There are WordPress plugins that have been identified known to conflict with the PHP session. I found out about these plugins when I upgraded a shopping cart plugin, eStore (by Tips and Tricks HQ), and noticed that the shopping cart wasn’t holding the correct inventory when moving from one page to another. Here is the list of widely used plugins that can cause conflicts with shopping carts, eStore specifically…
OZH’ Admin Drop Down Menu
Bad Behavior –
This plugin considers Paypal’s IPN as a form of spam and blocks it.
Maintenance Mode –
This plugin blocks all incoming data to website and shows landing page. May also prevent payment gateways from communicating and sending payment notification.
MailChimp Widget (just the plugin not the autoresponder)
Meebo for Sites –
This plugin is known to break shortcode functionality.
Revver Video WordPress Plugin –
Known to conflict with eMember.
WP Unique –
Shortcode code functionality breaks and works intermittently.
WordPress Firewall
this plugin can block another plugin’s admin menu that it believes is opening the ‘wp-admin.php’ file.
Google Analyticator –
Note: This plugin has been broken for sometime. Development for this plugin has recently been taken over by VideoUserManuals.com; and, many of the problems have been resolved. If you have an older version, be sure to upgrade to the latest. Instructions on how to install the newer version can be viewed HERE.
Custom Contact Form –
This contact form doesn’t use JQuery library properly. Use another contact form plugin.
Fluency Admin
Wibiya Toolbar –
This plugin break shortcode functionality.
wSecure Authentication
You can also use this plugin to test and make sure your theme is up to spec with the latest WordPress theme review standards:
http://wordpress.org/extend/plugins/theme-check/
