Title: Undefined Errors
Last modified: November 24, 2021

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# Undefined Errors

 *  Resolved [bkiehle](https://wordpress.org/support/users/bkiehle/)
 * (@bkiehle)
 * [4 years, 6 months ago](https://wordpress.org/support/topic/undefined-errors-4/)
 * Hello all,
 * we have been using the plugin for several years and have had no problems so far.
   But since a few weeks there is an error message when activating the plugin. However,
   only the error message bar is visible, there is no text. (Screenshot: [https://gw-wesel-flueren.de/wp-content/uploads/2021/11/empty_error_message_WP_SMTP.png](https://gw-wesel-flueren.de/wp-content/uploads/2021/11/empty_error_message_WP_SMTP.png)).
   I also sometimes have other errors on my page. For example, all links are displayed
   in blue (default Divi theme) instead of green or white.
 * Do you have any ideas?
 * Thanks a lot!
 * The page I need help with: _[[log in](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fwordpress.org%2Fsupport%2Ftopic%2Fundefined-errors-4%2F%3Foutput_format%3Dmd&locale=en_US)
   to see the link]_

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

 *  [shinerweb](https://wordpress.org/support/users/shinerweb/)
 * (@shinerweb)
 * [4 years, 6 months ago](https://wordpress.org/support/topic/undefined-errors-4/#post-15101359)
 * Has your host updated your PHP version or added in any MOD_SECURITY rules?
 * Are you seeing any errors in your browser console?
 *  Thread Starter [bkiehle](https://wordpress.org/support/users/bkiehle/)
 * (@bkiehle)
 * [4 years, 6 months ago](https://wordpress.org/support/topic/undefined-errors-4/#post-15104841)
 * There have been no changes in recent weeks. We use PHP 7.4 and WordPress 5.8.2.
 * I found a error message. Is it the WP Mail SMTP plugin? But the error does not
   occur when I disable Post SMTP.
 * `FastCGI sent in stderr: "PHP message: PHP Warning: sprintf(): Too few arguments
   in /home/wp/disk/wordpress/wp-content/plugins/wp-mail-smtp/src/Conflicts.php 
   on line 428" while reading response header from upstream, client: IP-ADRESS, 
   server: gw-wesel-flueren.de, request: "GET /wp-admin/plugins.php?activate=true&
   plugin_status=all&paged=1&s= HTTP/2.0", upstream: "fastcgi://unix:/var/run/wordpress.
   php-fpm.sock:", host: "gw-wesel-flueren.de", referrer: "https://gw-wesel-flueren.
   de/wp-admin/plugins.php"`
    -  This reply was modified 4 years, 6 months ago by [bkiehle](https://wordpress.org/support/users/bkiehle/).
 *  [shinerweb](https://wordpress.org/support/users/shinerweb/)
 * (@shinerweb)
 * [4 years, 6 months ago](https://wordpress.org/support/topic/undefined-errors-4/#post-15107869)
 * Did you see this: [PHP Warning](https://wordpress.org/support/topic/warning-when-conflicted-plugin/)
 * Looks like it could be something to do with translations/German Language file.
 *  Thread Starter [bkiehle](https://wordpress.org/support/users/bkiehle/)
 * (@bkiehle)
 * [4 years, 6 months ago](https://wordpress.org/support/topic/undefined-errors-4/#post-15109748)
 * Thank you very much!!!

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

The topic ‘Undefined Errors’ 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/)
 * [Frequently Asked Questions](https://wordpress.org/plugins/post-smtp/#faq)
 * [Support Threads](https://wordpress.org/support/plugin/post-smtp/)
 * [Active Topics](https://wordpress.org/support/plugin/post-smtp/active/)
 * [Unresolved Topics](https://wordpress.org/support/plugin/post-smtp/unresolved/)
 * [Reviews](https://wordpress.org/support/plugin/post-smtp/reviews/)

 * 4 replies
 * 2 participants
 * Last reply from: [bkiehle](https://wordpress.org/support/users/bkiehle/)
 * Last activity: [4 years, 6 months ago](https://wordpress.org/support/topic/undefined-errors-4/#post-15109748)
 * Status: resolved