Title: SendGrid list sync problem (libs/client.php not found)
Last modified: July 3, 2020

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# SendGrid list sync problem (libs/client.php not found)

 *  [adamanto](https://wordpress.org/support/users/adamanto/)
 * (@adamanto)
 * [6 years, 3 months ago](https://wordpress.org/support/topic/sendgrid-list-sync-problem-libs-client-php-not-found/)
 * Using SendGrid API, plugind failed to sync lists on locker creation screen. It
   throws exception:
    `PHP Fatal error: require_once(): Failed opening required '
   libs/client.php' (include_path='.:/usr/local/php/7.4/7.4.0-dh30/lib/php') in /
   home/[…]/public_html/wp-content/plugins/opt-in-panda/plugin/includes/subscription/
   sendgrid/class.sendgrid.php on line 49`
 * Solution:
    Change name of file opt-in-panda/plugin/includes/subscription/sendgrid/
   libs/Client.php to lowercase or fix it on line 49, because it does not works 
   on case-sensitive file systems.
    -  This topic was modified 6 years, 3 months ago by [adamanto](https://wordpress.org/support/users/adamanto/).

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 * 0 replies
 * 1 participant
 * Last reply from: [adamanto](https://wordpress.org/support/users/adamanto/)
 * Last activity: [6 years, 3 months ago](https://wordpress.org/support/topic/sendgrid-list-sync-problem-libs-client-php-not-found/)
 * Status: not resolved