Title: undismiss_core_update
Published: April 25, 2014
Last modified: May 20, 2026

---

# undismiss_core_update( string $version, string $locale ): bool

## In this article

 * [Parameters](https://developer.wordpress.org/reference/functions/undismiss_core_update/?output_format=md#parameters)
 * [Return](https://developer.wordpress.org/reference/functions/undismiss_core_update/?output_format=md#return)
 * [Source](https://developer.wordpress.org/reference/functions/undismiss_core_update/?output_format=md#source)
 * [Related](https://developer.wordpress.org/reference/functions/undismiss_core_update/?output_format=md#related)
 * [Changelog](https://developer.wordpress.org/reference/functions/undismiss_core_update/?output_format=md#changelog)

[ Back to top](https://developer.wordpress.org/reference/functions/undismiss_core_update/?output_format=md#wp--skip-link--target)

Undismisses core update.

## 󠀁[Parameters](https://developer.wordpress.org/reference/functions/undismiss_core_update/?output_format=md#parameters)󠁿

 `$version`stringrequired

`$locale`stringrequired

## 󠀁[Return](https://developer.wordpress.org/reference/functions/undismiss_core_update/?output_format=md#return)󠁿

 bool True if the option was updated, false otherwise.

## 󠀁[Source](https://developer.wordpress.org/reference/functions/undismiss_core_update/?output_format=md#source)󠁿

    ```php
    function undismiss_core_update( $version, $locale ) {
    	$dismissed = get_site_option( 'dismissed_update_core' );
    	$key       = $version . '|' . $locale;

    	if ( ! isset( $dismissed[ $key ] ) ) {
    		return false;
    	}

    	unset( $dismissed[ $key ] );

    	return update_site_option( 'dismissed_update_core', $dismissed );
    }
    ```

[View all references](https://developer.wordpress.org/reference/files/wp-admin/includes/update.php/)
[View on Trac](https://core.trac.wordpress.org/browser/tags/7.0/src/wp-admin/includes/update.php#L199)
[View on GitHub](https://github.com/WordPress/wordpress-develop/blob/7.0/src/wp-admin/includes/update.php#L199-L210)

## 󠀁[Related](https://developer.wordpress.org/reference/functions/undismiss_core_update/?output_format=md#related)󠁿

| Uses | Description | 
| [update_site_option()](https://developer.wordpress.org/reference/functions/update_site_option/)`wp-includes/option.php` |

Updates the value of an option that was already added for the current network.

  | 
| [get_site_option()](https://developer.wordpress.org/reference/functions/get_site_option/)`wp-includes/option.php` |

Retrieve an option value for the current network based on name of option.

  |

| Used by | Description | 
| [do_undismiss_core_update()](https://developer.wordpress.org/reference/functions/do_undismiss_core_update/)`wp-admin/update-core.php` |

Undismiss a core update.

  |

## 󠀁[Changelog](https://developer.wordpress.org/reference/functions/undismiss_core_update/?output_format=md#changelog)󠁿

| Version | Description | 
| [2.7.0](https://developer.wordpress.org/reference/since/2.7.0/) | Introduced. |

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