Title: PHP Warning: Undefined array key” HTTP_USER_AGENT
Last modified: March 25, 2021

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# PHP Warning: Undefined array key” HTTP_USER_AGENT

 *  Resolved [Gilou24](https://wordpress.org/support/users/gilou24/)
 * (@gilou24)
 * [5 years ago](https://wordpress.org/support/topic/php-warning-undefined-array-key-http_user_agent/)
 * Hello,
    I just want to report an error message in the error_log file : “PHP Warning:
   Undefined array key” HTTP_USER_AGENT “in xxx / wp-content / plugins / specific-
   content-for-mobile / specific-content-for -mobile.php on line 416 ” This message
   keeps appearing in this file…

Viewing 1 replies (of 1 total)

 *  Plugin Author [Jose Mortellaro](https://wordpress.org/support/users/giuse/)
 * (@giuse)
 * [5 years ago](https://wordpress.org/support/topic/php-warning-undefined-array-key-http_user_agent/#post-14233588)
 * thank you very much [@gilou24](https://wordpress.org/support/users/gilou24/)
 * Are you using WP CLI? It looks you aren’t using a browser.
 * In any case, this is fixed on the next version and the warning will not appear
   anymore even if HTTP_USER_AGENT is not defined.
 * Thank you again for reporting it.

Viewing 1 replies (of 1 total)

The topic ‘PHP Warning: Undefined array key” HTTP_USER_AGENT’ is closed to new replies.

 * ![](https://ps.w.org/specific-content-for-mobile/assets/icon-256x256.png?rev=
   2447531)
 * [Specific Content For Mobile - Customize the mobile version without redirections](https://wordpress.org/plugins/specific-content-for-mobile/)
 * [Support Threads](https://wordpress.org/support/plugin/specific-content-for-mobile/)
 * [Active Topics](https://wordpress.org/support/plugin/specific-content-for-mobile/active/)
 * [Unresolved Topics](https://wordpress.org/support/plugin/specific-content-for-mobile/unresolved/)
 * [Reviews](https://wordpress.org/support/plugin/specific-content-for-mobile/reviews/)

 * 1 reply
 * 2 participants
 * Last reply from: [Jose Mortellaro](https://wordpress.org/support/users/giuse/)
 * Last activity: [5 years ago](https://wordpress.org/support/topic/php-warning-undefined-array-key-http_user_agent/#post-14233588)
 * Status: resolved