The popular e-commerce plugin for WordPress, WooCommerce, though is a fork from another popular eCommerce plugin for WordPress Jigoshop, has quickly attracted its own followings and gained popularity. The ability of WooCommerce to transform the WordPress website into a full featured online eCommerce store while maintaining the WordPress’ hallmark for ease of use has set its apart from competition.
However, after installing WooCommerce plugin, or after activating a theme for WooCommerce, some webmasters get a rude shock that some or all of the WordPress admin pages no longer accessible. When attempting to visit WordPress admin dashboard, or when want to edit or post new post or page via edit.php and post-new.php, a blank page is displayed instead.
On debug error log, you may have the error lines similar to the following:
PHP Fatal error: Allowed memory size of 33554432 bytes exhausted (tried to allocate 47 bytes) in /.../wp-includes/meta.php on line 571
The error is caused by huge memory requirement of WooCommerce. Officially, WooCommerce requires at least 64MB of memory allocated to PHP to work correctly. Thus, the PHP memory limit has to be set to 64MB or higher.
To change the PHP memory limit, edit the php.ini configuration file (normally located in /etc, /usr/local/lib/php, /usr/lib and other common directory). Then, change the value for memory_limit to 64M (or higher). Lastly, restart the Apache (or any other web server that you use) to make the change effective.
Once the PHP memory limit is increased, you can access the WordPress admin pages without any issue.