Title: PHP Warning causing 500 error
Last modified: March 7, 2023

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# PHP Warning causing 500 error

 *  Resolved [zarinadev](https://wordpress.org/support/users/zarinadev/)
 * (@zarinadev)
 * [3 years, 2 months ago](https://wordpress.org/support/topic/php-warning-causing-500-error/)
 * Hi, I’m having a recurrent issue with a 500 error appearing on my site. I tried
   debugging via my site’s error log and these errors has been happening non stop
   for 4 days (these are the only errors on the error log so I’m assuming this is
   what causing my site to be down):
   PHP Warning: Undefined array key “optin_uuid”
   in /home3/marysalas/public_html/wp-content/plugins/mailoptin/src/core/src/AjaxHandler.
   php on line 1007PHP Warning: Undefined array key “stat_data” in /home3/marysalas/
   public_html/wp-content/plugins/mailoptin/src/core/src/AjaxHandler.php on line
   1006I was using PHP version 7.4 and have already updated to 8.1 some days ago,
   that’s the only change I’ve done to my site since this error started showing 
   up more frequently. Can you please provide a solution to this issue?Thanks in
   advance
 * The page I need help with: _[[log in](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fwordpress.org%2Fsupport%2Ftopic%2Fphp-warning-causing-500-error%2F%3Foutput_format%3Dmd&locale=en_US)
   to see the link]_

Viewing 3 replies - 1 through 3 (of 3 total)

 *  Thread Starter [zarinadev](https://wordpress.org/support/users/zarinadev/)
 * (@zarinadev)
 * [3 years, 2 months ago](https://wordpress.org/support/topic/php-warning-causing-500-error/#post-16538159)
 * I’ve temporarily disabled the plugin on my site to prevent the issue from happening
   again while we work on a solution to this.
 *  Plugin Author [Collins Agbonghama](https://wordpress.org/support/users/collizo4sky/)
 * (@collizo4sky)
 * [3 years, 2 months ago](https://wordpress.org/support/topic/php-warning-causing-500-error/#post-16539373)
 * PHP warning can’t cause a 500 error.
 * While we are going to fix them in the next release, please ensure you have WP_DEBUG
   set to false in wp-config.php file as you shouldn’t have it enabled (set to true)
   for a production or live site.
 *  Plugin Author [Collins Agbonghama](https://wordpress.org/support/users/collizo4sky/)
 * (@collizo4sky)
 * [3 years, 2 months ago](https://wordpress.org/support/topic/php-warning-causing-500-error/#post-16539414)
 * This has been fixed and will be available in the next plugin update slated for
   next week.

Viewing 3 replies - 1 through 3 (of 3 total)

The topic ‘PHP Warning causing 500 error’ is closed to new replies.

 * ![](https://ps.w.org/mailoptin/assets/icon-256x256.png?rev=1699978)
 * [MailOptin - Popup, Optin Forms & Email Newsletters for Mailchimp, HubSpot, AWeber Etc.](https://wordpress.org/plugins/mailoptin/)
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 * 3 replies
 * 2 participants
 * Last reply from: [Collins Agbonghama](https://wordpress.org/support/users/collizo4sky/)
 * Last activity: [3 years, 2 months ago](https://wordpress.org/support/topic/php-warning-causing-500-error/#post-16539414)
 * Status: resolved