Title: Default-filters.php error, upgrade not working
Last modified: August 19, 2016

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# Default-filters.php error, upgrade not working

 *  Resolved [sugaredharpy](https://wordpress.org/support/users/sugaredharpy/)
 * (@sugaredharpy)
 * [18 years, 1 month ago](https://wordpress.org/support/topic/default-filtersphp-error-upgrade-not-working/)
 * I am attempting to upgrade to 2.5 and I am now getting this error message on 
   my blog, [http://www.sugaredharpy.com](http://www.sugaredharpy.com):
 * Fatal error: Call to undefined function: add_filter() in /home/lilianaf/public_html/
   sugaredharpy/wp-includes/default-filters.php on line 20
 * I cannot run the WordPress upgrade script, I’ve checked other forum postings.
   I have not changed my wp-config.php.
 * Any help is appreciated!

Viewing 1 replies (of 1 total)

 *  Thread Starter [sugaredharpy](https://wordpress.org/support/users/sugaredharpy/)
 * (@sugaredharpy)
 * [18 years, 1 month ago](https://wordpress.org/support/topic/default-filtersphp-error-upgrade-not-working/#post-722655)
 * I have fixed the problem by again, and again EIGHT MORE TIMES uploading the files.
 * It should not take more than once or twice to upload an upgrade, though, to make
   it work. I’ve never had so many upgrade problems as this time.

Viewing 1 replies (of 1 total)

The topic ‘Default-filters.php error, upgrade not working’ is closed to new replies.

## Tags

 * [error code](https://wordpress.org/support/topic-tag/error-code/)
 * [upgrading](https://wordpress.org/support/topic-tag/upgrading/)

 * In: [Installing WordPress](https://wordpress.org/support/forum/installation/)
 * 1 reply
 * 1 participant
 * Last reply from: [sugaredharpy](https://wordpress.org/support/users/sugaredharpy/)
 * Last activity: [18 years, 1 month ago](https://wordpress.org/support/topic/default-filtersphp-error-upgrade-not-working/#post-722655)
 * Status: resolved

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