Mass email to users


Well-known member
Every now and then I send out a mass email to all of my site users on anything special like site updates etc. Not only does this help in getting users back to the site but it also helps me in cleaning out users that have not been to the site for a long time and their email address is no longer valid.

The problem is there is one isp that many of my users use that use Cisco's IronPort mail filtering appliance which stops all emails going to site users once x number of emails are sent to dead addresses.

Currently when I send out a mass email approx 10% bounce back yet many of those email addresses are valid but when the isp gets to a certain bounce back limit, they bounce back all subsequent emails even though the addresses are valid

I can't see any option in XF that will allow for batch email sending so I can send say 100 emails, wait till next day, send another 100 etc. OR is there any way around this to both send out a mass email and only get back the proper bounce backs of invalid email addresses?



XenForo developer
Staff member
If you're getting permanent failure messages, you'll want to take those users off from any email sending - probably by moving that to awaiting email confirmation. You will need to handle this manually.

If you're not getting the bounce messages, if you're using the standard PHP mail option, enable the -f parameter.


Well-known member
Thanks Mike
The bounced back messages I get from emails sent to users with that isp are:
SMTP error from remote mail server after initial connection:
host []:
550 Too many invalid recipients

So you can see that when it gets to too many invalid recipients ALL emails whether the addresses with that isp are valid or not receive that same message.

I sent a whole lot out and once it got to that "x" number with that isp anyone with valid email addresses with that isp did not receive the email


XenForo moderator
Staff member
That sounds like some sort of spam protection the ISP has implemented.

You may need to contact them to ensure you haven't been placed on a blacklist now.


Well-known member
Thanks Brogan
I did contact them and all they advised was:
Thank you for your email regarding the issues you have been experiencing with send email to bulk addresses.

Unfortunately we are able to confirm if a single or list of addresses are active or inactive due to privacy reasons.

Our only suggestion would be trying them in small blocks if possible, failing that sending emails one by one would be the only way to find out which are active and which are non-existent.

So, not much expected


XenForo developer
Staff member
I was referring to keeping your list up to date when you get the actual bounce failures so that when you do a bulk send, you get fewer bounces.

But this is a tricky issue - they're actually sending a permanent failure error as well, rather than a temporary error (which they should be doing). If it was a temporary error, your SMTP server should just handle it by resending over time.


Well-known member
I suggest using a sending agent such as Mandrill - it will identify bad email addresses and other mail delivery problems for you. You can use the reports to identify email addresses that require removal from your list.

If you have the skills to do so, you could even write a script to automate the processing of bounced email reports from Mandrill to clean your database from bad addresses. I have done this for vBulletin, but haven't yet ported it to XenForo (I use Mandrill for outbound email from my XenForo forums, but don't automatically process bounced reports back to the XenForo database yet).

It's free for up to 12,000 emails sent per month. Integration is via API or SMTP.