Title: undefined function
Last modified: August 31, 2016

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# undefined function

 *  Resolved [Dominic_N](https://wordpress.org/support/users/dominic_n/)
 * (@dominic_n)
 * [10 years, 4 months ago](https://wordpress.org/support/topic/undefined-function-11/)
 * After activating the plugin, the site returns the following error.
 * >  Fatal error: Call to undefined function get_rest_url() in C:\Abyss Web Server\
   > htdocs\wordpress\wp-content\plugins\rest-api\extras.php on line 24
 * [https://wordpress.org/plugins/rest-api/](https://wordpress.org/plugins/rest-api/)

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

 *  Thread Starter [Dominic_N](https://wordpress.org/support/users/dominic_n/)
 * (@dominic_n)
 * [10 years, 4 months ago](https://wordpress.org/support/topic/undefined-function-11/#post-6932895)
 * sorry. my mistake, the issue is the version of my wordpress core. the function
   `
   get_rest_url()` was added in 4.4 and mine was 4.3
 *  [odiliowew](https://wordpress.org/support/users/odiliowew/)
 * (@odiliowew)
 * [10 years, 4 months ago](https://wordpress.org/support/topic/undefined-function-11/#post-6932906)
 * Please tell me how to resolved that after install im can’t access dashboard thanks..
 *  Plugin Author [Daniel Bachhuber](https://wordpress.org/support/users/danielbachhuber/)
 * (@danielbachhuber)
 * [10 years, 4 months ago](https://wordpress.org/support/topic/undefined-function-11/#post-6932988)
 * > Please tell me how to resolved that after install im can’t access dashboard
   > thanks..
 * You’ll need to FTP (or similar) into your site to remove the plugin files.

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

The topic ‘undefined function’ is closed to new replies.

 * ![](https://ps.w.org/rest-api/assets/icon-256x256.png?rev=1346297)
 * [WordPress REST API (Version 2)](https://wordpress.org/plugins/rest-api/)
 * [Frequently Asked Questions](https://wordpress.org/plugins/rest-api/#faq)
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 * [Active Topics](https://wordpress.org/support/plugin/rest-api/active/)
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 * 3 replies
 * 3 participants
 * Last reply from: [Daniel Bachhuber](https://wordpress.org/support/users/danielbachhuber/)
 * Last activity: [10 years, 4 months ago](https://wordpress.org/support/topic/undefined-function-11/#post-6932988)
 * Status: resolved