Title: Guzzle integration causes fatal error Last modified: April 8, 2021 --- # Guzzle integration causes fatal error * [agaczub](https://wordpress.org/support/users/agaczub/) * (@agaczub) * [5 years ago](https://wordpress.org/support/topic/guzzle-integration-causes-fatal-error/) * Hi, there is a problem with this plugin – I’m using 1.5.3 version on the latest WordPress. The plugin causes fatal error after upgrade to the latest WP version. Currently the plugin is inactive. Reinstalling the plugin doestn’t help. * ``` Fatal error: Uncaught Error: Call to undefined method GuzzleHttp\Utils::chooseHandler() in /mysiteadresss.com/wp-content/plugins/woo-mailerlite/vendor/guzzlehttp/guzzle/src/functions.php:61 Stack trace: #0 /mysiteadresss.com/wp-content/plugins/backwpup/vendor/guzzlehttp/guzzle/src/HandlerStack.php(42): GuzzleHttp\choose_handler() #1 /mysiteadresss.com/wp-content/plugins/backwpup/vendor/guzzlehttp/guzzle/src/Client.php(65): GuzzleHttp\HandlerStack::create() #2 /mysiteadresss.com/wp-content/plugins/woo-mailerlite/vendor/mailerlite/mailerlite-api-v2-php-sdk/src/Common/RestClient.php(115): GuzzleHttp\Client->__construct() #3 /mysiteadresss.com/wp-content/plugins/woo-mailerlite/vendor/mailerlite/mailerlite-api-v2-php-sdk/src/Common/RestClient.php(47): MailerLiteApi\Common\RestClient->send() #4 /hmysiteadresss.com/wp-content/plugins/woo-mailerlite/vendor/guzzlehttp/guzzle/src/functions.php on line 61 ``` * Line 61 is “return Utils::chooseHandler();” in this fragment of code: * function choose_handler(): callable { return Utils::chooseHandler(); } * Thanks! Viewing 10 replies - 1 through 10 (of 10 total) * [ptm282192](https://wordpress.org/support/users/ptm282192/) * (@ptm282192) * [5 years ago](https://wordpress.org/support/topic/guzzle-integration-causes-fatal-error/#post-14293464) * The same issue here since yesterday update Please solve this asap Thank you! * [Krizsán Csaba](https://wordpress.org/support/users/csa3a07/) * (@csa3a07) * [5 years ago](https://wordpress.org/support/topic/guzzle-integration-causes-fatal-error/#post-14294436) * +1. Same issue here (until 1.5.0) I think it cause of update to WP 5.7. * [Slawek](https://wordpress.org/support/users/darcman86/) * (@darcman86) * [5 years ago](https://wordpress.org/support/topic/guzzle-integration-causes-fatal-error/#post-14312349) * Please provide solution. * Version – 1.5.3 * `Fatal error: Uncaught Error: Call to undefined method GuzzleHttp\Utils::chooseHandler() in /…/wp-content/plugins/woo-mailerlite/vendor/guzzlehttp/guzzle/src/functions. php:61 Stack trace: #0 /…/wp-content/plugins/backwpup/vendor/guzzlehttp/guzzle/ src/HandlerStack.php(42): GuzzleHttp\choose_handler() #1 /…/wp-content/plugins/ backwpup/vendor/guzzlehttp/guzzle/src/Client.php(65): GuzzleHttp\HandlerStack:: create() #2 /…/wp-content/plugins/woo-mailerlite/vendor/mailerlite/mailerlite- api-v2-php-sdk/src/Common/RestClient.php(115): GuzzleHttp\Client->__construct()# 3 /…/wp-content/plugins/woo-mailerlite/vendor/mailerlite/mailerlite-api-v2-php- sdk/src/Common/RestClient.php(59): MailerLiteApi\Common\RestClient->send(‘POST’,‘ woocommerce/sav…’, Array) #4 /…/wp-content/plugins/wo in /…/wp-content/plugins/ woo-mailerlite/vendor/guzzlehttp/guzzle/src/functions.php on line 61 * [Erik Almén](https://wordpress.org/support/users/almerika/) * (@almerika) * [5 years ago](https://wordpress.org/support/topic/guzzle-integration-causes-fatal-error/#post-14322909) * Same problem here. Any solutions? * [gerske](https://wordpress.org/support/users/gerske/) * (@gerske) * [5 years ago](https://wordpress.org/support/topic/guzzle-integration-causes-fatal-error/#post-14340734) * There is an update know to 1.5.4 * [Erik Almén](https://wordpress.org/support/users/almerika/) * (@almerika) * [5 years ago](https://wordpress.org/support/topic/guzzle-integration-causes-fatal-error/#post-14350097) * Works fine now. Thx. * [Eusebiu Oprinoiu](https://wordpress.org/support/users/eusebiuoprinoiu/) * (@eusebiuoprinoiu) * [5 years ago](https://wordpress.org/support/topic/guzzle-integration-causes-fatal-error/#post-14363806) * Same problem here. Waiting for an update! * [Eusebiu Oprinoiu](https://wordpress.org/support/users/eusebiuoprinoiu/) * (@eusebiuoprinoiu) * [5 years ago](https://wordpress.org/support/topic/guzzle-integration-causes-fatal-error/#post-14373589) * I just realized that the people before me say the issue is fixed in 1.5.4. For me, it isn’t. When WooCommerce Mailerlite is active, the plugin causes a fatal error in BackWPup (because of GuzzleHttp) and all my backups fail. The error can also be seen on the settings page of BackWPup, on the tab which controls the remote destination. (in my case Amazon S3) * My guess is you are using the library without namespacing it and this clashes with other plugins that use it. Pixel Caffeine had the same problem a few months ago. * [Nicholas Zein](https://wordpress.org/support/users/zeinnicholas/) * (@zeinnicholas) * [4 years, 12 months ago](https://wordpress.org/support/topic/guzzle-integration-causes-fatal-error/#post-14411875) * I can confirm the issue persists and when contacting MailerLite’s support they informed me they are aware of the issue and are working to fix it. * [Nicholas Zein](https://wordpress.org/support/users/zeinnicholas/) * (@zeinnicholas) * [4 years, 9 months ago](https://wordpress.org/support/topic/guzzle-integration-causes-fatal-error/#post-14669871) * The issue still persists with the current version 1.5.5. Viewing 10 replies - 1 through 10 (of 10 total) The topic ‘Guzzle integration causes fatal error’ is closed to new replies. * ![](https://ps.w.org/woo-mailerlite/assets/icon-256x256.png?rev=3083985) * [MailerLite - WooCommerce integration](https://wordpress.org/plugins/woo-mailerlite/) * [Frequently Asked Questions](https://wordpress.org/plugins/woo-mailerlite/#faq) * [Support Threads](https://wordpress.org/support/plugin/woo-mailerlite/) * [Active Topics](https://wordpress.org/support/plugin/woo-mailerlite/active/) * [Unresolved Topics](https://wordpress.org/support/plugin/woo-mailerlite/unresolved/) * [Reviews](https://wordpress.org/support/plugin/woo-mailerlite/reviews/) * 10 replies * 8 participants * Last reply from: [Nicholas Zein](https://wordpress.org/support/users/zeinnicholas/) * Last activity: [4 years, 9 months ago](https://wordpress.org/support/topic/guzzle-integration-causes-fatal-error/#post-14669871) * Status: not resolved