Postman: wp_mail has been declared by another plugin or theme

Hi @phyton,

Please paste a copy of your Post SMTP diagnostics log in your next reply – this may help us to identify your issue.

If you have any custom code, such as in functions.php or a child theme – please disable this first to ensure that is not the problem.

Kind Regards,
Tim

The first web site of Diagnostic test:

Mailer: postsmtp
HostName: websitename.com
cURL Version: 7.29.0
OpenSSL Version: NSS/3.53.1
OS: Linux SONYEDEK333 3.10.0-1160.25.1.el7.x86_64 #1 SMP Wed Apr 28 21:49:45 UTC 2021 x86_64
PHP: Linux 7.4.20 C
PHP Dependencies: iconv=Yes, spl_autoload=Yes, openssl=Yes, sockets=Yes, allow_url_fopen=Yes, mcrypt=Yes, zlib_encode=Yes
WordPress: 5.7.2 tr_TR UTF-8
WordPress Theme: Medina
WordPress Plugins: WPML Multilingual CMS, Advanced Custom Fields, Akismet Anti-Spam, Contact Form 7, Disable Gutenberg, Enable Media Replace, Header and Footer Scripts, Loco Translate, NinjaFirewall (WP Edition), Post SMTP, Really Simple SSL, Redirection, Compress JPEG & PNG images, Advanced Editor Tools (previously TinyMCE Advanced), Unyson, WordPress Importer, Yoast SEO Premium, Yoast SEO, WP-Optimize Premium - Clean, Compress, Cache
WordPress wp_mail Owner: /home/websitename.com/public_html/wp-content/plugins/post-smtp/Postman/PostmanWpMailBinder.php
WordPress wp_mail Filter(s): wp_staticize_emoji_for_email, PostsmtpMailer->get_mail_args
WordPress phpmailer_init Action(s): wpcf7_phpmailer_init
Postman: 2.0.23
Postman Sender Domain (Envelope|Message): websitename.com | websitename.com
Postman Prevent Message Sender Override (Email|Name): No | No
Postman Active Transport: Gmail API (https:oauth2://www.googleapis.com:443)
Postman Active Transport Status (Ready|Connected): Yes | Yes
Postman Deliveries (Success|Fail): 664 | 12

The second one:

Mailer: postsmtp
HostName: websitename.com
cURL Version: 7.29.0
OpenSSL Version: NSS/3.53.1
OS: Linux SONYEDEK333 3.10.0-1160.25.1.el7.x86_64 #1 SMP Wed Apr 28 21:49:45 UTC 2021 x86_64
PHP: Linux 7.4.20 C
PHP Dependencies: iconv=Yes, spl_autoload=Yes, openssl=Yes, sockets=Yes, allow_url_fopen=Yes, mcrypt=Yes, zlib_encode=Yes
WordPress: 5.7.2 tr_TR UTF-8
WordPress Theme: SEOCrawler Child
WordPress Plugins: Coming Soon Page, Maintenance Mode & Landing Pages by SeedProd, Contact Form 7, Disable Gutenberg, Enable Media Replace, Envato Market, Goodlayers Personnel Post Type, Goodlayers Portfolio Post Type, Goodlayers Twitter, Goodlayers Core, Header and Footer Scripts, NinjaFirewall (WP Edition), Post SMTP, Really Simple SSL, Redirection, Slider Revolution, Webcraftic Robin image optimizer, Compress JPEG & PNG images, Yoast SEO, WP Google Map Plugin, WP-Optimize Premium - Clean, Compress, Cache
WordPress wp_mail Owner: /home/websitename.com/public_html/wp-content/plugins/post-smtp/Postman/PostmanWpMailBinder.php
WordPress wp_mail Filter(s): wp_staticize_emoji_for_email, PostsmtpMailer->get_mail_args
WordPress phpmailer_init Action(s): wpcf7_phpmailer_init, PostsmtpMailer->phpmailer_smtp_init
Postman: 2.0.23
Postman Sender Domain (Envelope|Message): websitename.com | websitename.com
Postman Prevent Message Sender Override (Email|Name): No | No
Postman Active Transport: SMTP (smtps:plain://smtp.yandex.com:465)
Postman Active Transport Status (Ready|Connected): Yes | Yes
Postman Deliveries (Success|Fail): 282 | 1

Hi @phyton,

I can’t see anything glarignly obvious, thanks for providing the logs.

Did you try disabling all plugins except Post SMTP to see if the error clears?

Kind Regards,
Tim

That’s very weird, but when I disable wp optimize cache, the problem disappeared.

Hi @phyton,

Interesting! Must be some kind of conflict. Does the issue come back when you re-enable WP Optimize Cache?

Kind Regards,
Tim

Yes. I have removed wp optimize in one of my web site, and the error not came again.

I also open a ticket to wp optimize, they said: “WP-Optimize doesn’t use wp_mail function, Could you please disable other plugins except WP-Optimize and check if it helps to fix the issue.

If the issue is fixed, you can enable the the plugins one by one until the issue re-appears so we know the plugin which is conflicting.”

This really weird, but I have the same error in the other web site because I haven’t remove wp optimize on there.

• This reply was modified 3 years, 5 months ago by M-POWER.

Hi @phyton,

Are you sure that it is definitely the WP-Optimize plugin?

I agree with their support team that their plugin shouldn’t/doesn’t use wp_mail.

If you re-enable WP-Optimize, does Post SMTP stop working again?

Kind Regards,
Tim

Post smtp are working in the both situations. I see the errors in the log files. When I deactivated Wp Optimize, The error disappeared.

For example, I use another cache at the web site for 2-3 days and I haven’t seen the error again for this web site.

You can see the error log file:

https://ibb.co/M2FF9nD

Hi @phyton,

This is certainly very strange, I’ll flag this to the plugin developer. Please be aware that he is not able to reply to everyone, but I am sure will look at this.

Kind Regards,
Tim

@yehudah – odd conflict on some environments with WP-Optimize

Okay thank you.

The issue is still alive.