BuddyPress.org

Hey BuddyPress community,

I’m experiencing a recent prevalence of failed activation emails with my BuddyPress installation. I am not an expert with PHP mail() or other SMTP issues, and I would love some advice on how better to diagnose the issue. Here is some relevant info:

• WordPress 3.8.1
• BuddyPress 1.9.2 (also in Trunk)
• Nginx + PHP5.5 + Memcached
• Google Apps email handling

My site is experiencing a period of very high growth, with between 150-200 attempted user registrations each day. On a typical day, most of these are successful. Activation emails are sent without a hitch, and accounts are activated normally. However, around 40-50 attempted activations are failing each day.

Some of these are (of course) due to typos in email addresses. Some are due to failure on behalf of the user to follow activation instructions. Some failures may even be due to spam filtering by the user’s email client.

I know for a fact, however, that a non-trivial number of these emails are simply failing to reach the recipient. On an average day I receive around 10 contact form inquiries from users who did not receive their activation email, and yet they provided a valid (and correct) email address. They have checked their spam folders and filters, and nothing was screened out.

Obviously, this is imposing an administration cost of dealing with manual account activations. It’s additionally costing me a lot of potential users who don’t go to the trouble to solicit help. This is a situation that I VERY MUCH would like to resolve ASAP, so that user registration on my site can proceed normally. If any of you have any insight into things I could try in order to diagnose the exact issue it would be hugely appreciated.

To provide a bit more additional info: there are a multitude of email domains for which this issue seems to be occurring, however I am frequently seeing this happen with non-mainstream email hosts.

• Hosts like gmx, live, web, bk, btinternet and others seem commonly filtered.
• Gmail, AOL, charter, and other “mainstream” hosts show up less frequently than I would expect given their market shares.
• .edu recipients get filtered a lot, but this is probably due to university policies and an unrelated issue.

Some other information that may be helpful is that I use DKIM and SPF keys (both of which are properly configured in DNS).

Anyways, I realize this is a very niche issue and may be difficult to resolve, but if there are any email experts out there I would really love to make progress on this, as I’m having to spend around 30 minutes per day dealing with users who are unable to activate (not to mention all the non-vocal user accounts which my site is losing).

Please let me know if I can provide any information to help better diagnose the issue!

Andrew