Title: Fatal Error – setClassMapAuthoritative
Last modified: August 6, 2018

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# Fatal Error – setClassMapAuthoritative

 *  Resolved [Jos Klever](https://wordpress.org/support/users/josklever/)
 * (@josklever)
 * [7 years, 9 months ago](https://wordpress.org/support/topic/fatal-error-setclassmapauthoritative/)
 * Hi David,
 * Another site, another error. Probably a conflict with another plugin, but we 
   did a rollback to version 3.0.6, to get the site back online and I didn’t have
   the time yet to investigate the issue. Do you have any idea, what this could 
   be? (PHP 7.1)
 * `Fatal error: Uncaught Error: Call to undefined method Composer\Autoload\ClassLoader::
   setClassMapAuthoritative() in /********/wp-content/plugins/mollie-payments-for-
   woocommerce_/includes/mollie-api-php/vendor/composer/autoload_real.php:38 Stack
   trace: #0 /********/wp-content/plugins/mollie-payments-for-woocommerce_/includes/
   mollie-api-php/vendor/composer-autoload.php(7): ComposerAutoloaderInit4062f91c07f6f2ba911ecd0f0813a468::
   getLoader() #1 /********/wp-content/plugins/mollie-payments-for-woocommerce_/
   includes/mollie-api-php/vendor/autoload.php(5): require_once('********...') #
   2 /********/wp-content/plugins/mollie-payments-for-woocommerce_/mollie-payments-
   for-woocommerce.php(25): require_once('********...') #3 /********/wp-admin/includes/
   plugin.php(1897): include('******** in /********/wp-content/plugins/mollie-payments-
   for-woocommerce_/includes/mollie-api-php/vendor/composer/autoload_real.php on
   line 38`

Viewing 2 replies - 1 through 2 (of 2 total)

 *  Plugin Contributor [davdebcom](https://wordpress.org/support/users/davdebcom/)
 * (@davdebcom)
 * [7 years, 9 months ago](https://wordpress.org/support/topic/fatal-error-setclassmapauthoritative/#post-10567001)
 * It will take some more time to investigate this with Mollie in the Mollie API
   PHP client. So I reverted the changes. Please update to 4.0.2 which I just released.
   Also see:
    [https://github.com/mollie/WooCommerce/wiki/Composer-Guzzle-conflicts](https://github.com/mollie/WooCommerce/wiki/Composer-Guzzle-conflicts)
 *  Thread Starter [Jos Klever](https://wordpress.org/support/users/josklever/)
 * (@josklever)
 * [7 years, 9 months ago](https://wordpress.org/support/topic/fatal-error-setclassmapauthoritative/#post-10567047)
 * Updated to 4.0.2 and the site is still working. Good luck with the investigation!

Viewing 2 replies - 1 through 2 (of 2 total)

The topic ‘Fatal Error – setClassMapAuthoritative’ is closed to new replies.

 * ![](https://ps.w.org/mollie-payments-for-woocommerce/assets/icon-256x256.png?
   rev=3090580)
 * [Mollie Payments for WooCommerce](https://wordpress.org/plugins/mollie-payments-for-woocommerce/)
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 * 2 replies
 * 2 participants
 * Last reply from: [Jos Klever](https://wordpress.org/support/users/josklever/)
 * Last activity: [7 years, 9 months ago](https://wordpress.org/support/topic/fatal-error-setclassmapauthoritative/#post-10567047)
 * Status: resolved