Title: Warning: Undefined global variable $_SESSION
Last modified: March 11, 2024

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# Warning: Undefined global variable $_SESSION

 *  Resolved [yuluma](https://wordpress.org/support/users/yuluma/)
 * (@yuluma)
 * [2 years, 3 months ago](https://wordpress.org/support/topic/warning-undefined-global-variable-_session/)
 * Dear Mailgun dev,
   Since the last update we get the following notice in all our
   updated sites/shops.
 * **Warning**: Undefined global variable $_SESSION in **/xxxxx/wp-content/plugins/
   mailgun/includes/admin.php** on line **340**
 * **Warning**: Trying to access array offset on value of type null in **/xxxxx/
   plugins/mailgun/includes/admin.php** on line **340**
 * WP_DEBUG is switched off, this notice only appears on the WP backend, on top 
   of every page.
 * We use version: 1.9.8 for all sites that have the display of this warning.

Viewing 2 replies - 1 through 2 (of 2 total)

 *  [DistrictOperator](https://wordpress.org/support/users/districtoperator/)
 * (@districtoperator)
 * [2 years, 2 months ago](https://wordpress.org/support/topic/warning-undefined-global-variable-_session/#post-17497719)
 * I have the same issue and submitted it on the Mailgun support site.
 * They told me to go on the Settings page and change “Use HTTP API” to No.
 * This did **not** solve the warning.
 *  [DistrictOperator](https://wordpress.org/support/users/districtoperator/)
 * (@districtoperator)
 * [2 years, 2 months ago](https://wordpress.org/support/topic/warning-undefined-global-variable-_session/#post-17510259)
 * I just updated to version 1.9.9 and am no longer receiving this PHP warning.
 * Thanks Mailgun!

Viewing 2 replies - 1 through 2 (of 2 total)

The topic ‘Warning: Undefined global variable $_SESSION’ is closed to new replies.

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## Tags

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

 * 2 replies
 * 2 participants
 * Last reply from: [DistrictOperator](https://wordpress.org/support/users/districtoperator/)
 * Last activity: [2 years, 2 months ago](https://wordpress.org/support/topic/warning-undefined-global-variable-_session/#post-17510259)
 * Status: resolved