I am sorry that I have to come back to this, but there is still one provider that is still showing the issue, even with version 2.3 of post smtp active.
Problematic configuration seems to be: PHP 8.x, No SMTP (out of the box configuration)
This happens only on the shared hosting of ONE provider (Hetzner) so far. All other previously problematic sites seem to work with the new version.
This is the diagnostic test:
Mailer: postsmtp
HostName: kuechekaufen.com
cURL Version: 7.74.0
OpenSSL Version: OpenSSL/1.1.1n
OS: Linux dedi2804.your-server.de 5.10.0-19-amd64 #1 SMP Debian 5.10.149-1 (2022-10-17) x86_64
PHP: Linux 8.0.26 C
PHP Dependencies: iconv=Yes, spl_autoload=Yes, openssl=Yes, sockets=Yes, allow_url_fopen=No, mcrypt=Yes, zlib_encode=Yes
WordPress: 6.1.1 de_DE UTF-8
WordPress Theme: GeneratePress Kind
WordPress Plugins: ManageWP - Worker, Post SMTP, Advanced Custom Fields PRO, Beaver Builder Plugin (Developer Version), Beaver Themer, PowerPack for Beaver Builder, Classic Editor, Clean Image Filenames, Admin Columns, Fluent Forms, Fluent Forms Pro Add On Pack, GP Premium, HappyFiles Pro, Central Color Palette, Custom Functions for Scherer, WP Grid Builder, WP Photo Sphere, SEOPress PRO, SEOPress, WPvivid Plugins Pro, WPvivid Backup Plugin
WordPress wp_mail Owner: /usr/www/users/xxxxx/wp-content/plugins/post-smtp/Postman/PostmanWpMailBinder.php
WordPress wp_mail Filter(s): wp_staticize_emoji_for_email, PostsmtpMailer->get_mail_args
Postman: 2.2.3
Postman Sender Domain (Envelope|Message): problematic-domain.de | problematic-domain.de
Postman Prevent Message Sender Override (Email|Name): No | No
Postman Active Transport: Standard (smtp:none:none://localhost:25)
Postman Active Transport Status (Ready|Connected): No | Yes
Postman Deliveries (Success|Fail): 5 | 0
Postman Stealth Mode: Yes
Do you have any suggestion, what I might do, to fix this? Can’t use SMTP sadly.
Using the fixed beta version helps, but none of the newer versions works.
Regards
Anja