I’m surely not a professional – so maybe my question is quite silly.
I have a small list of 248 members of a chess club; I sent a newsletter and got the confirmation that 149 out of 149 Newsletter were sent.
All members are activated, confirmed and so on – I do not have any idea why they do not get the newsletter.
Anyone any hint?
Standard delivery with wp_mail() script is sometimes limited to 100 mails per hour (ask you wp provider). No visible error for the non delivered mails. You can reduce the number of mails per hour or install a SMTP addon (the number of mails per hour can be different, ask our email provider).
I had similar problem with other transactional emails, and to address these often not clear issues I recommend you install WP MAIL SMTP plugin.
This has a detailed log of sent mails, and in case there are errors also detailed information about what happened.
With it I could prove to my hosting provider that the mails bounced on his SMTP server – as per policy, there was 100/hour limit.
As we sometimes had peak hours with more that 100/hour, we ran into this issue.
After explaining the situation to support, and proving it’s transaction mails, and not some spam, the settings were changed to Per Day and not Per Hour.
Since then, all is great 🙂