System is down today, only sending 10-25% of the proper amount of mail

Quick note: Tech Support needs to the delivery system today as it's not sending out to 100%.

First time it's done this in a month, everything to this point has been flawless but for some reason today it's having issues.

Just re-sent the campaign again to confirm the problem, nearly the same result, only 20-25% of the emails that should go out are actually being sent.

Mathew Mathew, 4 years ago


Sorry for your trouble. To be clear, we are sending out 100% of the emails, but we are seeing some delays in delivery. There are many different reasons that emails can be sent, but not arrive immediately.

From what we can tell at this stage, it is a combination of very high sending volumes and mail service delays. What we see during these periods is that we can push email out from our servers much faster than some of the major email systems (like Gmail and Yahoo) can accept it at certain times.

So the emails back up a little as our servers retry to make the connection. During very high volume periods (like now, before Thanksgiving) that can mean some emails get delayed between us queuing them up to send and the recipient's server being able to take them.

We realise this doesn't make it any better from your side, but I wanted to be clear that it isn't something we can immediately fix for you. We have multiple ways of improving things from our side (spreading email across more servers, moving campaigns around and the like) and we're also already working on increasing capacity.

These aren't instant fixes unfortunately; adding more capacity is easy but we need to do it in a way that protects deliverability, and so it can take a while to ramp up. We started some time ago, and we're part way through that process.

Sorry again for the trouble, please be assured we take this very seriously and in as much as we can control it from our side, we're doing what needs to be done. The rest  is up to the email services and normal email delays unfortunately.

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BraceRosso, 4 years ago

So if a client is complaining that emails aren't arriving in their own inboxes (for 2 campaigns sent yesterday)... it's possible that the reason is that they were never delivered?

I'll be sending in a support email to check on this.

Mathew Mathew, 4 years ago

No, most likely if the email has not arrived at all, there is a spam filtering issue, or some other problem - what I was describing above is more like the email takes a couple of hours before it shows up.

Sorry for the confusion.

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CM88, 4 years ago

Thanks Matthew.

The problem though is that the emails being sent to the biggest providers (Gmail, Yahoo) aren't just not getting there in a timely way...they're actually not being delivered at all (even 48 hours after the send).

So it might be more than a backed-up-for-the-holidays issue, it's may have more to do with actual deliverability on CM's part. 

Love this service, perfect fit for my business, but it definitely may be time to expand/upgrade to match CM's higher volumes now.


Mathew Mathew, 4 years ago


Emails not being delivered at all is a different issue really; we'd need to investigate that on a case by case basis, because we can see tons of email opens being recorded at gmail and Yahoo, as per normal.

There doesn't seem to be an overall deliverability issue to either of those providers, and we do have monitoring in place to catch these kinds of things. If you can contact us with more specific details about your campaign and an address that hasn't received it, we can follow up with you on that.

As I mentioned, we already are upgrading our systems too, to deal with the other issue of slower delivery times, and we appreciate your feedback.

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