Title: Warning Undefined array key “SERVER_NAME”
Last modified: January 19, 2026

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# Warning Undefined array key “SERVER_NAME”

 *  [Johannes Kingma](https://wordpress.org/support/users/abrioofgkcibzcueldxk/)
 * (@abrioofgkcibzcueldxk)
 * [4 months, 2 weeks ago](https://wordpress.org/support/topic/warning-undefined-array-key-server_name-3/)
 * We received the following warning message:
 * Probably as the result of a cron job calling wp-cron.php
 *     ```wp-block-code
       PHP Warning:  Undefined array key "SERVER_NAME" in /home/server/wp-content/plugins/multiple-domain-mapping-on-single-site/multidomainmapping.php on line 81
       ```
   
 * The page I need help with: _[[log in](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fwordpress.org%2Fsupport%2Ftopic%2Fwarning-undefined-array-key-server_name-3%2F%3Foutput_format%3Dmd&locale=en_US)
   to see the link]_

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to reply to this topic.

 * ![](https://ps.w.org/multiple-domain-mapping-on-single-site/assets/icon-256x256.
   png?rev=1595238)
 * [Multiple Domain Mapping on Single Site](https://wordpress.org/plugins/multiple-domain-mapping-on-single-site/)
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## Tags

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

 * 0 replies
 * 1 participant
 * Last reply from: [Johannes Kingma](https://wordpress.org/support/users/abrioofgkcibzcueldxk/)
 * Last activity: [4 months, 2 weeks ago](https://wordpress.org/support/topic/warning-undefined-array-key-server_name-3/)
 * Status: not resolved