Title: Error 500 API
Last modified: May 8, 2026

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# Error 500 API

 *  [lucasgoro1](https://wordpress.org/support/users/lucasgoro1/)
 * (@lucasgoro1)
 * [1 month, 2 weeks ago](https://wordpress.org/support/topic/error-500-api/)
 * Hello,
 * I’m having an issue with the Woo MailerLite plugin version 3.1.16 on WordPress.
 * When I try to connect the API key inside the plugin settings, the connection 
   fails and returns a 500 Internal Server Error.
 * What I already checked:
    - PHP version: 8.2.30
    - WordPress REST API is working correctly (`/wp-json/` works fine)
    - Debug mode enabled in WordPress
    - API key regenerated from MailerLite
    - Plugin reinstalled
 * The error happens immediately after clicking the API connect button.
 * Is this a known issue or compatibility problem with recent WordPress/PHP versions?
 * Thanks.
 * The page I need help with: _[[log in](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fwordpress.org%2Fsupport%2Ftopic%2Ferror-500-api%2F%3Foutput_format%3Dmd&locale=en_US)
   to see the link]_

Viewing 1 replies (of 1 total)

 *  Plugin Support [algutalml](https://wordpress.org/support/users/algutalml/)
 * (@algutalml)
 * [1 month, 2 weeks ago](https://wordpress.org/support/topic/error-500-api/#post-18904357)
 * Thanks for letting us know about this! To help you out, we’ll need to gather 
   some sensitive information that we can’t handle here on the forum. Could you 
   please get in touch with us directly [here](https://www.mailerlite.com/contact-us?category=woocommerce-wordpress-shopify)?
   
   When filling out the form, please add the code WP Forum or simply mention that
   you were advised to reach out from the forum. This way, we’ll be able to assist
   you faster and more effectively.

Viewing 1 replies (of 1 total)

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 * ![](https://ps.w.org/woo-mailerlite/assets/icon-256x256.png?rev=3083985)
 * [MailerLite - WooCommerce integration](https://wordpress.org/plugins/woo-mailerlite/)
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 * 1 reply
 * 2 participants
 * Last reply from: [algutalml](https://wordpress.org/support/users/algutalml/)
 * Last activity: [1 month, 2 weeks ago](https://wordpress.org/support/topic/error-500-api/#post-18904357)
 * Status: not resolved