To configure the UWS Scheduler Add-on, it is recommended that you deactivate the default WordPress cron scheduler mechanism and replace it with a job scheduler, such as cron, called from your operating system or from your ISP’s dashboard or from an external site such as Pingdom.

Step 1 – disable the default WordPress cron

To disable the default WordPress cron, edit the wp-config.php file adding the following line, placed where all of the other DEFINE statements are located:

define('DISABLE_WP_CRON', true);

Step 2 – add a new cron job

The scheduler extension needs to be called at regular intervals to check whether there are any scheduled messages to send. To call the plugin script, a command needs to be called every few minutes from an external scheduler, such as cron (on Linux) or Task Manager (from Windows). If your WordPress hosting company uses cpanel, then follow the steps described here  to configure a cron job. It is recommended that the cron job runs every 5 minutes.

If you do have access to cron, then create a job to run the following command:

wget -q -O - >/dev/null 2>&1

If you do not have access to cpanel or a similar scheduler, then you can call the UWS Message Scheduler from Pingdom’s free monitoring service. Configure the free Pingdom monitor to call

The free Pingdom service will call the UWS Message Scheduler a minimum of every 15 minutes, meaning that some messages you’ve scheduled may be sent up to 15 minutes later than scheduled. If you need more accurate scheduling then consider Pingdom’s paid-for services.

Assistance can be provided with these configuration steps by emailing

These changes are recommended but not mandated. The changes are recommended because WordPress checks whether any jobs are scheduled when someone visits your site, not at regular time intervals. For example, you may have scheduled some messages to be sent a 2am. Using the default WordPress scheduler, if someone visits your website at around 2am, then WordPress will run the schedule. If nobody visits your site until 8am, then the messages will not be sent until 8am. If you have the time and inclination this article explains this in more detail.