Title: Fix “Undefined variable: output”
Last modified: June 20, 2020

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# Fix “Undefined variable: output”

 *  [invokers](https://wordpress.org/support/users/invokers/)
 * (@invokers)
 * [5 years, 11 months ago](https://wordpress.org/support/topic/fix-undefined-variable-output/)
 * If you have display errors and notices turn on in PHP you will receive the following
   notice which you can of course ignore but it will make the robot.txt file invalid.
 * Error:
    <b>Notice</b>: Undefined variable: output in <b>……/wp-content/plugins/
   multisite-robotstxt-manager/inc/classes/class-robotstxt.php</b> on line <b>92
   </b><br />
 * To fix this:
    Edit the following file:
 * /wp-content/plugins/multisite-robotstxt-manager/inc/classes/class-robotstxt.php
 * After Line 89: $public = get_option( ‘blog_public’ );
 * Add the following code:
 * $output = ”;
 * Thanks for the great plugin.

The topic ‘Fix “Undefined variable: output”’ is closed to new replies.

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 * 0 replies
 * 1 participant
 * Last reply from: [invokers](https://wordpress.org/support/users/invokers/)
 * Last activity: [5 years, 11 months ago](https://wordpress.org/support/topic/fix-undefined-variable-output/)
 * Status: not a support question