Hello @kennet1975
We hope this message finds you well.
Thank you for reaching out to our Support team. We’re truly sorry to hear that you’ve encountered this issue.
To assist you effectively could you please share the Diagnostic test report with us?
Also with the sites facing the issues, have you been able to identify any common factor, like a security plugin or an email service provider perhaps?
I await your response & an opportunity to assist you.
Warm regards,
[ Signature deleted, don’t do that here, OK? ]
Hello
No security or email service provider issue.
Here is the report
Mailer: phpmailer
HostName: hyrbilengavle.se
cURL Version: 7.29.0
OpenSSL Version: NSS/3.90
OS: Linux server.pregalmedia.se 3.10.0-1160.119.1.el7.x86_64 #1 SMP Tue Jun 4 14:43:51 UTC 2024 x86_64
PHP: Linux 8.3.12 C
PHP Dependencies: iconv=No, spl_autoload=Yes, openssl=Yes, sockets=Yes, allow_url_fopen=Yes, mcrypt=No, zlib_encode=Yes
WordPress: 6.9 sv_SE UTF-8
WordPress Theme: OceanWP Child
WordPress Plugins: Ocean Extra, Classic Editor, Classic Widgets, Elementor Pro, Elementor, Head & Footer Code, WP Armour – Honeypot Anti Spam, OMGF, MainWP Child Reports, MainWP Child, Ocean Elementor Widgets, Ocean Social Sharing, Ocean Sticky Header, Ocean White Label, Patchstack Security, Post SMTP, Fixed Widget, Rank Math SEO, UpdraftPlus – Backup/Restore, VikRentCar, Visual Portfolio, Posts & Image Gallery, WP Reset PRO
WordPress wp_mail Owner: /home/gavlehybil/domains/hyrbilengavle.se/public_html/wp-includes/pluggable.php
WordPress wp_mail Filter(s): wp_staticize_emoji_for_email, PostsmtpMailer->get_mail_args
Postman: 3.6.2
Postman Sender Domain (Envelope|Message): hyrbilengavle.se | hyrbilengavle.se
Postman Prevent Message Sender Override (Email|Name): Yes | Yes
Postman Active Transport: Standard (smtp:none:none://localhost:25)
Postman Active Transport Status (Ready|Connected): No | Yes
Postman Deliveries (Success|Fail): 22333 | 23
Hey @kennet1975 ,
Thank you for sharing these details & please accept our apologies for the delayed response.
Based on the details, the issue is not with security or your email provider, it is caused by Post SMTP falling back to localhost (smtp:none:none://localhost:25) instead of using your actual SMTP settings. This results in errors like Sender verify failed and MAIL FROM command failed.
When you disable the plugin, WordPress uses the default PHP mail function, which is why sending works.
This started after recent updates where incomplete SMTP setups are no longer allowed to fall back silently. Your current configuration shows:
- No valid SMTP server selected
- No authentication
iconv extension missing (may also affect behavior)
To resolve this, Reconfigure your SMTP settings in Post SMTP (select your real SMTP provider, enter host, port, username/password) and save. After that, run a connectivity test.
Warm regards,
[ Signature deleted, don’t do that here, OK? ]
Hello
Thanks! That solved the issue on most of my sites, but not all. One.com email account still problems:
https://help.one.com/hc/en-us/articles/115005594305-Can-I-use-your-SMTP-server-to-send-emails
Hey @kennet1975,
I’m glad to hear that most of the issues have been resolved.
Could you please share the exact error message you’re encountering with the One.com email accounts? Additionally, please test the configuration using our tool and let me know if any error message appears there as well.
Once I have those details, I’ll be happy to look into it further.
Warm regards,
[ Signature deleted, don’t do that here, OK? ]
Hello
Yes this error message
You getting this message because an error detected while delivered your email.
För domänen: https://hyrbilengavle.se
Loggen att klistra in när du öppnar ett supportärende:
The following From address failed: [email protected] : MAIL FROM command failed,[M9] User [[email protected]] not authorized to send on behalf of <[email protected]> (e7367c7c-d39f-11f0-a5a5-fb5fec76084d)
,550,5.7.1 SMTP server error: MAIL FROM command failed Detail: [M9] User [[email protected]] not authorized to send on behalf of <[email protected]> (e7367c7c-d39f-11f0-a5a5-fb5fec76084d)
SMTP code: 550 Additional SMTP info: 5.7.1
And test tool:
{ “success”: 1, “result”: { “accepted”: [ “[email protected]” ], “rejected”: [], “envelopeTime”: “<[email protected]>”, “messageTime”: “<[email protected]>”, “messageSize”: 53, “response”: “221 2.0.0 Bye\r\n”, “envelope”: { “from”: “[email protected]”, “to”: [ “[email protected]” ] }, “messageId”: “<[email protected]>” } }
Thank you so much for sharing it with me.
The error happens because your SMTP user ([email protected]) isn’t authorized to send as [email protected].
To fix this ensure that “Prevent plugin & theme from changing this” is checked in Post SMTP> Settings> Messages tab.
If issue still exists:
SPF/DKIM/DMARC must also allow this if sending “on behalf of” another address.
Hello @kennet1975 ,
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,
[ Signature deleted, don’t do that here, OK? ]
Hello
Yes understand, but we are not sending “on behalf of” nothing other than our noreply account. Several of our other sites also has this issue. The plugin automticly change the “from” address (often to [email protected]) even though “Prevent plugin & theme from changing this” is checked in Post SMTP> Settings> Messages tab.
Regards Ken
