Bug #10678

Newsletter Plugin Not Sending Out Newsletters

Added by Mark Webb 3 months ago. Updated 22 days ago.

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The Newletter plugin for the CPCP website ( is again having issues. Newsletters are not sending out. You then have to go in and manually run the queue but this takes forever and stops on its own unless you go back and run again. Any idea what is happening? Is it related to the WP Cron? How can we fix it? Thanks,



#1 Updated by Boone Gorges 3 months ago

  • Status changed from New to Reporter Feedback

Hi Mark - I am unfamiliar with the way that this Newsletter plugin works. Could you please provide me with more specific details about what you're doing, and how it's supposed to work?

I see but I don't understand whether these are items that have already sent. When you say you have to "go in and manually run the queue", what exactly are you doing? And when you say it "takes forever and stops on its own", exactly what is happening? Does "takes forever" mean that the page hangs after you click a button? Or does it mean that emails send in the background, but only one at a time, and there's a long pause between? Or perhaps an initial batch (of 20 or whatever) is sent right away, but the next one never happens? When you say "again having issues", do you mean that you've had this specific problem in the past? If it's just started, could you please indicate when was the last time it worked as intended, and when you noticed it stopped working? (We had some performance issues throughout the day today, which may be related.)

The more details you can provide, the easier it will be for me to try pinpointing the issue.

#2 Updated by Mark Webb 3 months ago

When I say "again" I am simply referring to the fact that my last bug report was in reference to the same plugin.

So, I actually don't know how this plugin in normally works as I am working on behalf of the CPCP who sends these newsletters out and asked me to look into what the problem is now. Now when you go to send a newsletter the option to click at the bottom right is "queue newsletter." You click on that and it takes you to the "email queue" page where you have the option to "run now" which presumably would send the newsletter to all of the emails in the queue. But when you click "run now" it takes you to a blank page with a url that ends in "scheduled tasks." It is unclear what is happening on this page. It seems that the first few batches of emails send but then it stops. You then have to go back and hit "run now" again but even that eventually stops doing anything (as in you can't even hit "run now" to manually send all of the batches). I understand that when you click "queue newsletter" it should automatically start sending out batches. I am told the problem started a little over a week ago and was noticed after 3-4 newsletters did not go out and were just left in the queue.

#3 Updated by Boone Gorges 3 months ago

Hi Mark - Thanks very much for the additional info, which helps me narrow down what's happening.

We do not use WP's built-in cron system - which is why you see the notice through the Newsletters admin about 'DISABLE_WP_CRON' - but we have a replacement system service called Cavalcade that is responsible for asynchronous tasks. I can see from my logs that the most recent scheduled queue-send event was marked "failed", but this could mean many things, and my guess is that it means that the process started successfully but didn't complete - as in, perhaps it ran for too long and couldn't be shut down. This meshes with your comment that some emails seem to be sent, but then the process dies for one reason or other.

The first thing I'd suggest trying is to reduce the batch size. See "Emails per interval" at Try something low, like 20, and then trigger another batch. This might be enough to allow the Newsletters plugin to complete its task, and then properly schedule the next one.

If this doesn't work, I'll need to do some more active debugging, which means I'll need to be able to press the "go" button on an email queue batch. Before I'm comfortable doing that, I need to have a better understanding of the plugin interface. This page has almost 4000 items in the "queue", but the "Date" column suggests that they've already been processed/sent. Do you have a sense of what's happening here? The timestamps (from last night and this morning) suggest that they correspond to times when you, or another member of the team, has manually triggered email sending. Is that correct? Can you point me toward a specific URL and a specific button I can hit, without being fearful of double-sending an email?

#4 Updated by Boone Gorges 3 months ago

  • Target version set to Not tracked

#5 Updated by Mark Webb about 1 month ago

Hi Boone,

This issue has popped up again. For whatever reason the queue starting backing up again and was not sending out emails automatically. I am currently manually hitting "run now" on the queue and have been playing around with different queue sizes, but I have no idea what the source of the problem is. We did recently switch the template we are using in newsletter but I don't know why that would make a difference. Thanks for the help!

#6 Updated by Boone Gorges about 1 month ago

Hi Mark - Could you provide some more detail on what's happened recently?

- You mentioned that it "popped up again" - does that mean it'd been working as expected?
- When did you first notice that it wasn't working again?
- Does the queue contain items from more than one newsletter, or just a single one?
- Does the plugin appear to have sent any items automatically?
- When you hit "run now", does it process a single batch, or multiple batches before stopping?
- When did you switch the template?

#7 Updated by Mark Webb 22 days ago

Thanks Boone,

Things seem to be working again. Perhaps something triggers when the queue gets backed up preventing things from functioning smoothly? Why the queue got backed up in the first place is still a mystery to me.

We noticed the problem when we tried to send out a newsletter a couple of weeks ago. We just switched the template before the holidays and this was the second newsletter sent with the new template. I don't do the newsletters, I am just working on smoothing out the hitches with the site and newsletter, so I was contacted when the newsletter queue was already backed up with 4,000 emails and it was not sending out anything unless I ran it manually, one batch at a time (it would send one or half of one, depending on the size, and then stop).


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