Title: PHP Warnings “failed to read session data: memcache”
Last modified: August 24, 2017

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# PHP Warnings “failed to read session data: memcache”

 *  Resolved [passer13](https://wordpress.org/support/users/passer13/)
 * (@passer13)
 * [9 years, 1 month ago](https://wordpress.org/support/topic/php-warnings-failed-to-read-session-data-memcache/)
 * Plugin v.4.6.0 PHP 7.1
    Have a lot of warnings: `PHP Warning: session_start():
   Failed to read session data: memcache (path: tcp://localhost:11211) in .../wp-
   content/plugins/shortpixel-image-optimiser/class/wp-short-pixel.php on line 21"
   while reading response header from upstream`
 * After enabled this line in wp-shortpixel.php
    `define('SHORTPIXEL_DEBUG', true);`
 * got also in my error.log:
 *     ```
       PHP message: INIT: Session queue not found, updated from Options with []
       PHP message: QUEUE: processing(): get:[]
       PHP message: CHECK QUOTA: Skipped: """
       PHP message: INIT: Session queue not found, updated from Options with []" while reading response header from upstream..
       ```
   

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

 *  Plugin Author [ShortPixel](https://wordpress.org/support/users/shortpixel/)
 * (@shortpixel)
 * [9 years, 1 month ago](https://wordpress.org/support/topic/php-warnings-failed-to-read-session-data-memcache/#post-9438451)
 * Hi,
    thanks for your message, sorry to hear about this issue.
 * It looks like your server uses memcache for keeping sessions and they aren’t 
   properly configured, you may want to check this link for a possible solution:
   [https://stackoverflow.com/questions/24184568/php-sessions-not-being-saved-in-memcache](https://stackoverflow.com/questions/24184568/php-sessions-not-being-saved-in-memcache)
 * Regards,
    Alex
 *  Thread Starter [passer13](https://wordpress.org/support/users/passer13/)
 * (@passer13)
 * [9 years, 1 month ago](https://wordpress.org/support/topic/php-warnings-failed-to-read-session-data-memcache/#post-9439109)
 * Thanks for an idea! The problem solved.
 *  Plugin Author [ShortPixel](https://wordpress.org/support/users/shortpixel/)
 * (@shortpixel)
 * [9 years, 1 month ago](https://wordpress.org/support/topic/php-warnings-failed-to-read-session-data-memcache/#post-9440563)
 * Great, thanks for the follow-up! 🙂

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

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 * ![](https://ps.w.org/shortpixel-image-optimiser/assets/icon-256x256.gif?rev=3245715)
 * [ShortPixel Image Optimizer - Optimize Images, Convert WebP & AVIF](https://wordpress.org/plugins/shortpixel-image-optimiser/)
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 * 3 replies
 * 2 participants
 * Last reply from: [ShortPixel](https://wordpress.org/support/users/shortpixel/)
 * Last activity: [9 years, 1 month ago](https://wordpress.org/support/topic/php-warnings-failed-to-read-session-data-memcache/#post-9440563)
 * Status: resolved