Title: Notification sending error
Last modified: March 21, 2025

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# Notification sending error

 *  Resolved [Aleksander Eerma](https://wordpress.org/support/users/alexeerma/)
 * (@alexeerma)
 * [1 year, 2 months ago](https://wordpress.org/support/topic/notification-sending-error/)
 * Hey! 
   I got an error like this on email. ->You are getting this message because
   an error detected while delivered your email.For the domain: [https://mydomain.com](https://domain.com)
   The log to paste when you open a support issue:Missing To header What might be
   the issue? When I try to test, the emails get there and wont fail. I suspect 
   the error has to do with a events plugin, and when users register to my event,
   I should get a notification e-mail, but right now I am getting this error.

Viewing 4 replies - 1 through 4 (of 4 total)

 *  Plugin Support [M Aqib Khan](https://wordpress.org/support/users/aqibkhan9/)
 * (@aqibkhan9)
 * [1 year, 2 months ago](https://wordpress.org/support/topic/notification-sending-error/#post-18375156)
 * Hello @alexeerma ,
 * We hope this message finds you well.
 * Thank you for reaching out to our Support team. We are concerned to hear about
   the issue you’re facing and sincerely regret any inconvenience caused.
 * The email you received was sent from our server because issues were detected 
   while delivering your email through your configured email service provider.
 * The error message seems to be due to missing “To email”, as you have pointed 
   out that this happens with the emails send through a particular plugin, could
   you please share the name of the plugin? Perhaps sharing the Diagnostic test 
   report will allow us to reproduce a similar environment as yours’s and assist
   you effectively.
 * Looking forward to your response & an opportunity to assist you.
 * Warm regards,
   Support Team – WP Experts
 *  Thread Starter [Aleksander Eerma](https://wordpress.org/support/users/alexeerma/)
 * (@alexeerma)
 * [1 year, 2 months ago](https://wordpress.org/support/topic/notification-sending-error/#post-18378090)
 * Hey! 
   The name of the plugin is registrations for the events calendar. This is
   the diganostics test.
 *     ```wp-block-code
       Mailer: postsmtpHostName: etfl.eecURL Version: 8.4.0OpenSSL Version: OpenSSL/1.1.1wOS: Linux sn-69-30.tll07.zoneas.eu 5.15.138-zoneos #1 SMP Wed Nov 15 10:55:18 -00 2023 x86_64PHP: Linux 8.3.16 C.UTF-8PHP Dependencies: iconv=Yes, spl_autoload=Yes, openssl=Yes, sockets=Yes, allow_url_fopen=Yes, mcrypt=No, zlib_encode=YesWordPress: 6.7.2 et UTF-8WordPress Theme: Brandweb ChildWordPress Plugins: Query Monitor, LayerSlider, Advanced Custom Fields Multilingual, Advanced Custom Fields PRO, Algori PDF Viewer Lite, Core Rollback, Duplicator, Email Templates, Embed PDF Viewer, Event Tickets, Grids, WPCode Lite, Koko Analytics, HubSpot All-In-One Marketing - Forms, Popups, Live Chat, Max Mega Menu, Ninja Forms - User Management, Ninja Forms, PDF Block, Post SMTP, Prevent Direct Access, Registrations for The Events Calendar, Search & Replace, Search & Filter Pro, WPML Multilingual CMS, The Events Calendar, Wordfence Security, WordPress Importer, Yoast SEO, WP All Export, WP Fastest Cache, WP Media folder, WP Rollback, WPML SEO, WPForms, WPML Media Translation, WPML String Translation, WPForms MultilingualWordPress wp_mail Owner: /data01/virt59371/domeenid/www.etfl.ee/htdocs/wp-content/plugins/post-smtp/Postman/PostmanWpMailBinder.phpWordPress wp_mail Filter(s): wp_staticize_emoji_for_email, PostsmtpMailer->get_mail_args, Mailtpl_Mailer->send_emailWordPress wp_mail_from Filter(s): wordfence::fixWPMailFromAddress, Mailtpl_Mailer->set_from_emailWordPress wp_mail_from_name Filter(s): Mailtpl_Mailer->set_from_nameWordPress wp_mail_content_type Filter(s): Mailtpl_Mailer->set_content_typePostman: 3.1.3Postman Prevent Message Sender Override (Email|Name): No | NoPostman Active Transport: Default (smtp:none:none://localhost:25)Postman Active Transport Status (Ready|Connected): No | YesPostman Deliveries (Success|Fail): 3191 | 20
       ```
   
 *  Plugin Support [M Aqib Khan](https://wordpress.org/support/users/aqibkhan9/)
 * (@aqibkhan9)
 * [1 year, 2 months ago](https://wordpress.org/support/topic/notification-sending-error/#post-18380654)
 * Hey [@alexeerma](https://wordpress.org/support/users/alexeerma/)
 * Thank you so much for sharing the requested information. I replicated a similar
   scenario as yours & especially [Registrations for the Events Calendar](https://wordpress.org/plugins/registrations-for-the-events-calendar/)
   plugin, but wasn’t able to reproduce it on my end. Kindly ensure that the email
   settings are correctly configured in the plugin.
 * Kindly, deactivate all plugins except Post SMTP & revert to basic theme like 
   Twenty-Twenty Five. To see if the issue is due to the conflict with any other
   plugin.
 * This will help us narrow down the issue.
 * Warm regards,
   Support Team – WP Experts
 *  Plugin Support [M Aqib Khan](https://wordpress.org/support/users/aqibkhan9/)
 * (@aqibkhan9)
 * [1 year, 2 months ago](https://wordpress.org/support/topic/notification-sending-error/#post-18392107)
 * Hello @alexeerma ,
 * We hope you are doing well.
 * We are marking this thread as resolved due to inactivity. If you encounter any
   further issues, please feel free to open a new thread.
 * Have a great day!
 * Thanks and regards,
   Support Team – WP Experts

Viewing 4 replies - 1 through 4 (of 4 total)

The topic ‘Notification sending error’ is closed to new replies.

 * ![](https://ps.w.org/post-smtp/assets/icon-128x128.gif?rev=3209655)
 * [Post SMTP – Complete Email Deliverability and SMTP Solution with Email Logs, Alerts, Backup SMTP & Mobile App](https://wordpress.org/plugins/post-smtp/)
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 * 4 replies
 * 2 participants
 * Last reply from: [M Aqib Khan](https://wordpress.org/support/users/aqibkhan9/)
 * Last activity: [1 year, 2 months ago](https://wordpress.org/support/topic/notification-sending-error/#post-18392107)
 * Status: resolved