Troubleshooting failed delivery


Does ActiveCampaign have any generalized advice or tools for troubleshooting eMail delivery issues? I deliver a course through an automation. The overall deliverability is just fine, but when a subscriber contacts me because they haven’t received the eMail it gets tricky.

I do all the obvious things - ask them to check spam, add our sending eMail address to their safe list and resend the eMail. But they never receive the eMail (a manual test from my own eMail address - same domain, different eMail account) reaches them just fine. I do not see any indication within ActiveCampaign that the automation eMail bounced.

Just looking for some input on how to investigate further - “tough luck” isn’t a great message to deliver :slight_smile:




Hi Mark,

Here’s the section of our help docs on deliverability:

If it becomes a recurring concern, you could also open a support ticket if you want our team to investigate what happened. They may have some advice on how to prevent the same issue in the future.


@perfectbee Mark, we also just created this help center article which explores the various reasons an email might bounce (not be delivered) which should help you troubleshoot the various problems that might cause an email to not be delivered:


Thank you both. Interestingly, the issues I am seeing (at least in terms of subscribers contacting me) are never flagged as bounces in Active Campaign. In all cases “something” has happened at their end, presumably with spam.

I had someone today who swore blind she didn’t get it but eventually found it in junk. But she moved it to her Inbox - and it disappeared again. She looked in junk and her inbox but there was no trace. I have no idea what happened there. The previous eMails in our automation were nowhere to be seen, including junk.

Unfortunately, it’s these types of issues that are toughest to track down because I’m reliant on an informed subscriber. The subscriber starts with the assumption that it’s our problem and so contacts us. My demographic is rather old (on average) and often less tech-savvy.

It’s a difficult balance of being there for the customer vs. being clear when it’s outside of our control. So I am eager to bring some process to this, which is why I asked.



Thanks for bringing up this topic, @perfectbee!
I’m currently encountering issues with emails not being received by people with Hotmail addresses. Most importantly, these people aren’t receiving their opt-in confirmation emails when they join a list…so they are unable to complete the subscription process. Nor do they receive the lead magnet they’ve requested. Frustrating for both sides, I’m certain.
I feel like I’ve read every article on email deliverability but am still unsure how I can improve this issue. Hoping something might come to light through this topic stream.


WE have been seeing the same thing lately and support confirmed that there were issues on AC side. The emails were getting backed up and our automation was unsubscribing them from the list for example before the automation was able to send out the email. We had to set one of the campaigns to 3 hours delay for unsubscribe. It took numerous support emails to get to the bottom of it and we are still dealing w/ some of the issues. I would ask support to look deeper.



Slightly off topic but we turned off confirmation eMails about a year ago. The loss of folks due to entry of bad eMail addresses (who wouldn’t get the confirmation eMail anyway) was significantly lower than the loss of folks who received the confirmation eMail but never bothered to respond.

The confirmation eMail is just another barrier to having a signed up subscriber and removing that barrier helped a lot.



Thanks, @perfectbee!
Unfortunately, the double opt-in process is pretty much required here in Canada due to our anti-spam laws. For those countries who have less tight rules, definitely a great suggestion and one I wish I could follow. :slight_smile:
Thank you!


We are having the same issues since we started with AC, we raise a ticket, they “fix” it and after a couple of months the problems are back…


Hi all ! all emails we sent to hotmail inboxes are not being received. This happens with automations and also with all the emails we send from AC.

We detected this some weeks ago. At the beginning some emails were received but with two or more days of delay and others would never reach the inbox. Since some days NO emails are being received at all. This happens only with hotmail addresses. We have no problems with gmail or private domains, at least for now…

We raise a ticket and we are a solution, in the meantime we would appreciate help to solve the problem.




@vivilasfotos Hotmail/Outlook has been making major changes to their infrastructure over the past 2-3 months merging Office365 and Outlook infrastructure, and adding a lot of new places where users can click “this is spam” which is really changing the way their spam filters behave and causing a lot more deliverability issues for everyone. Here are 2 really relevant articles that explain the greater picture:

Oh, Microsoft
Microsoft changes
Microsoft ‘Moves’ to Make Reporting Junk Email Easier

The bottom line with deliverability issues like this is that you should reach out to There are various levers we can pull to help you out in many cases, and we can advise you on the best course of action.


Thanks @aburch the support team just fix the problem!


At least I see that is not only my account that has been having issues, I raised a ticket but I’m still waiting for a solution. I do not find a pattern here, there are hotmail and gmail accounts.