Title: “Undefined offset” PHP error message
Last modified: December 30, 2018

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# “Undefined offset” PHP error message

 *  Resolved [zeevmodality](https://wordpress.org/support/users/zeevmodality/)
 * (@zeevmodality)
 * [7 years, 5 months ago](https://wordpress.org/support/topic/undefined-offset-php-error-message/)
 * Hi,
 * I get the following error while using total cache with PHP 7.1 , ubuntu 16 :
 * 2018/12/30 06:15:27 [error] 1410#1410: *46056 FastCGI sent in stderr: “PHP message:
   PHP Warning: Cannot assign an empty string to a string offset in ***/wp-includes/
   class.wp-scripts.php on line 426
    PHP message: PHP Warning: Cannot assign an 
   empty string to a string offset in ***/wp-includes/class.wp-scripts.php on line
   426 PHP message: PHP Notice: Undefined offset: 1 in ***/wp-content/plugins/w3-
   total-cache/Cache_Memcached.php on line 74” while reading response header from
   upstream, client: 37.142.41.68, server: elastic.walabot.com, request: “GET /wp-
   admin/admin.php?page=w3tc_support HTTP/1.1”, upstream: “fastcgi://unix:/run/php/
   php7.1-fpm.sock:”, host: “***”, referrer: “***/wp-admin/plugins.php”
 * The memcache server is configured with port number so the error is not explained
 * Can you advice if the error affect the functionality and how to resolve ?
 * Thanks

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

 *  Plugin Contributor [Marko Vasiljevic](https://wordpress.org/support/users/vmarko/)
 * (@vmarko)
 * [7 years, 4 months ago](https://wordpress.org/support/topic/undefined-offset-php-error-message/#post-11052402)
 * Hello,
    As I can see in the code, you did not specify the port number. You should
   have something like `127.0.0.1:11211` and you are missing the `:11211`. Have 
   you configured Memcache itself with the port number, or within the plugin? This
   does not affect the functionality but memcached is not used now because there
   is no server added to the Memcached handler At least not correctly, so I think
   nothing will be added to the memcached server
 *  Thread Starter [zeevmodality](https://wordpress.org/support/users/zeevmodality/)
 * (@zeevmodality)
 * [7 years, 4 months ago](https://wordpress.org/support/topic/undefined-offset-php-error-message/#post-11055678)
 * Hi Marko,
 * As I mentioned in the post , the memcache server do configured with port
 * It looks like this :
 * XXX.YYY.0001.euc1.cache.amazonaws.com:11211
 * Any idea ?
 * I am not sure I understood your question “Have you configured Memcache itself
   with the port number, or within the plugin?”
    The memcache configuration is in
   the databases cache settings / Advanced settings
 * Thanks
 *  Plugin Contributor [gidomanders](https://wordpress.org/support/users/gidomanders/)
 * (@gidomanders)
 * [7 years, 4 months ago](https://wordpress.org/support/topic/undefined-offset-php-error-message/#post-11063598)
 * [@zeevmodality](https://wordpress.org/support/users/zeevmodality/) Marko means
   that you must provide a port number in the W3 Total Cache settings. As the error
   tells us, you didn’t include the `:11211` part (it cannot find the `:` so it 
   cannot split the setting into URL and port number). We do not specify a default
   port number to fall back on.

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

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## Tags

 * [php](https://wordpress.org/support/topic-tag/php/)

 * 3 replies
 * 3 participants
 * Last reply from: [gidomanders](https://wordpress.org/support/users/gidomanders/)
 * Last activity: [7 years, 4 months ago](https://wordpress.org/support/topic/undefined-offset-php-error-message/#post-11063598)
 * Status: resolved