Some servers set a limit on the number of emails that could be sent per hour.


arpReach is designed to manage such host limits, all you have to do is ask your web host what your hourly sending limit is and follow the guidelines below. Everything will run on autopilot from then on.


Let's say your server only allows 500 emails to be sent per hour. The solution is to change some settings so that no more than 500 emails per hour get sent by arpReach. arpReach then will automatically manage sending 500 emails per hour until all due emails have gone out.


There are 2 settings to change to ensure that you comply to the limit — the run frequency of your scheduled task (cron job) for the arpReach script AND (in arpReach) your email system's 'Send limit per run':


Scheduled task (cron job)

We recommend setting the run frequency of your scheduled task (cron job) for the arpReach script every 5 minutes. You can change this in your cPanel by changing its "minutes" setting to */5.


This means that the sending of emails will also occur every 5 minutes, whenever the arpReach script runs, totaling to 12 runs per hours.


Because you are limited to 500 emails per hour, you need to ensure that each of those runs sends no more than 41 emails. 


Here’s a quick formula that you can use:


(hourly limit) / (no. of cron job runs in an hour)

500 / 12 = 41.67


Send limit per run (in arpReach)

Now, go to your email system settings in arpReach and go to Options / Advanced. 


Set the ‘Send limit per run’ slightly lower than 41. For example, 38.


Note: We’ve always been recommending to setting the ‘Delay between each email’ to zero (0), since setting it to a high number would not only slow the sending but also cause timeouts. If there really is a need for a delay between each email, it should be set to a low number and make sure that your server’s MySQL timeout can handle it.


Setting the ‘Send limit per run’ value slightly lower (i.e., 38 instead of 41) gives way to immediate/unscheduled messages (such as subscription confirmation emails and single emails triggered by actions).