500 internal server error

Hello, I have a website since many years. The configuration and plugins are the same since ages. Just updates are being done regularly. After I update the mailerlite API key from classic to new MailerLite I started receiving complains by people that the forms are not working. I tested them and they work if the subscribe to newsletter is unchecked. People that select the checkbox get a 500 error. FYI: the API key is updated (the new one) on both MailerLite official plugin, as well as in CF7 connector. In the Connector application logs and Debug logs there are some entries related to bots and empty email addresses, but there are no entry for the specific attempts to send a normal contact form by me or other people (not robots). No errors in webserver error log. In access log there is a 500 172.68.139.85 - - www.anahatatantra.com [24/Jan/2024:12:41:15 +0100] "POST /wp-json/contact-form-7/v1/contact-forms/5924/feedback HTTP/2.0" 500 292 "https://www.anahatatantra.com/contacts/" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36" "myip(hidden)" The error happens on: https://www.anahatatantra.com/contacts/ https://www.anahatatantra.com/pl/kontakt/ https://www.anahatatantra.com/book-a-tantric-massage/ https://www.anahatatantra.com/pl/rezerwacja-masaz-tantryczny/ Please freely try to send contact form – you can put “test” as name. Please kindly help This topic was modified 2 years, 4 months ago by utnalove . Hi Could you check PHP error log? It helps to understand why and where the error occurs. You can also temporary install and enable “WP Debugging” plugin (or similar) to see error message. Thank you for the quick reply. Here is the debug: [24-Jan-2024 11:49:10 UTC] PHP Fatal error: Uncaught Error: Call to undefined function GuzzleHttp\choose_handler() in /mypath//wp-content/mods/ari-cf7-connector/cf7_addons/mailerlite/libraries/vendor/vendor/php-http/guzzle6-adapter/src/Client.php:75 Stack trace: #0 /mypath//wp-content/mods/ari-cf7-connector/cf7_addons/mailerlite/libraries/vendor/vendor/php-http/guzzle6-adapter/src/Client.php(36): Http\Adapter\Guzzle6\Client::buildClient() #1 /mypath//wp-content/mods/ari-cf7-connector/cf7_addons/mailerlite/libraries/vendor/vendor/php-http/discovery/src/ClassDiscovery.php(219): Http\Adapter\Guzzle6\Client->__construct() #2 /mypath//wp-content/mods/ari-cf7-connector/cf7_addons/mailerlite/libraries/vendor/vendor/php-http/discovery/src/Psr18ClientDiscovery.php(30): Http\Discovery\ClassDiscovery::instantiateClass() #3 /mypath//wp-content/mods/ari-cf7-connector/cf7_addons/mailerlite/libraries/vendor/vendor/mailerlite/mailerlite-api-v2-php-sdk/src/Common/RestClient.php(14 in /mypath//wp-content/mods/ari-cf7-connector/cf7_addons/mailerlite/libraries/vendor/vendor/php-http/guzzle6-adapter/src/Client.php on line 75 It looks like a conflict with another plugin. We can investigate the problem in more details, but it will require a temporary access to admin part. You can contact us: info (at) ari-soft (dot) com sent. Please check Try now please. It was a problem with “Autopay” plugin. We installed “ARI MailerLite Fix” plugin as “Must User” plugin to resolve the problem. Yes it works, thank you. How to go for a fix, not workaround? Is it something you will fix in some future release, or Autopay has to fix it? The problem occurred because different versions of the same library are used by the plugins. “ARI MailerLite Fix” plugins prevents loading of “Autopay” when CF7 form is processing. You can find the plugin in wp-content/mu-plugins folder. Just copy it to another site to the same folder if need a fix on another site. Thank you. How can I send a fix request to Autopay. Can they do something so that I can remove in future “ARI MailerLite Fix” ? Unfortunately we don’t familiar how it works, but we suppose it loads all their library on each WordPress page even when it is not necessary. We guess they can load them only for WooCommerce pages. Hello, I have contacted the Autopay support and they analyzed the code and wrote me back that the Contact Form 7 Connector plugin seems to have some problem with ajax because it has not only problems with Autopay but also with other plugins such as: 'woo-mailerlite/woo-mailerlite.php', 'op-dashboard/op-dashboard.php', 'connector-gravityforms-mailerlite/connector-gravityforms-mailerlite.php', 'ameliabooking/ameliabooking.php', 'themeisle-companion/themeisle-companion.php', 'platnosci-online-blue-media/bluemedia-woocommerce.php', Can you please take a look at it and find a way to make the plugin work without excluding such big plugins? The helper plugin doesn’t totally exclude the plugins. It is only exclude them when handle requests from CF7 form which these plugins are not handled and they shouldn’t be loaded to improve performance. Can’t you make the plugin to avoid conflicts with other plugins? In other words, avoid getting 500 internal server errors without excluding other plugins when handle requests from CF7. The problem is some 3rd party plugins use different versions of shared libraries. We will remove some dependencies in a future version. BTW, number of dependencies from 3rd party libraries are decreased in. v. 1.2.4