Title: Fatal Error message
Last modified: August 19, 2016

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# Fatal Error message

 *  Resolved [jenmorrison](https://wordpress.org/support/users/jenmorrison/)
 * (@jenmorrison)
 * [16 years, 10 months ago](https://wordpress.org/support/topic/fatal-error-message-12/)
 * I have made a mistake. I was attempting to remedy a missing element in my WordPress
   application. I noticed that some files seemed to be missing from the wp-includes
   folder, so I re-uploaded the folder from my files, replacing the previous files.
   Now my site won’t load, instead I get this message:
 * Fatal error: Call to undefined function add_filter() in C:\inetpub\vhosts\realia.
   ca\httpdocs\wordpress\wp-includes\default-filters.php on line 20

Viewing 5 replies - 1 through 5 (of 5 total)

 *  [ryans149](https://wordpress.org/support/users/ryans149/)
 * (@ryans149)
 * [16 years, 10 months ago](https://wordpress.org/support/topic/fatal-error-message-12/#post-1179035)
 * make sure you uploaded the files from correct version… also, make sure all the
   files were uploaded.
 * Also, check this:
 * `add_filter($filter, 'strip_tags');`
 * there should not be any space within this tag..
 *  Thread Starter [jenmorrison](https://wordpress.org/support/users/jenmorrison/)
 * (@jenmorrison)
 * [16 years, 10 months ago](https://wordpress.org/support/topic/fatal-error-message-12/#post-1179037)
 * I don’t see
    add_filter($filter, ‘strip_tags’);
 * is that supposed to be in the wp-includes folder?
 *  [ryans149](https://wordpress.org/support/users/ryans149/)
 * (@ryans149)
 * [16 years, 10 months ago](https://wordpress.org/support/topic/fatal-error-message-12/#post-1179048)
 * yes, this line should be there.. it is in the standard wordpress installation..
   which version are you using?
 *  Thread Starter [jenmorrison](https://wordpress.org/support/users/jenmorrison/)
 * (@jenmorrison)
 * [16 years, 10 months ago](https://wordpress.org/support/topic/fatal-error-message-12/#post-1179050)
 * 2.6.3
 * I’m not finding it in any of the folders. That’s strange.
 *  Thread Starter [jenmorrison](https://wordpress.org/support/users/jenmorrison/)
 * (@jenmorrison)
 * [16 years, 10 months ago](https://wordpress.org/support/topic/fatal-error-message-12/#post-1179195)
 * I have found that tag, and there are no spaces.

Viewing 5 replies - 1 through 5 (of 5 total)

The topic ‘Fatal Error message’ is closed to new replies.

## Tags

 * [fatal](https://wordpress.org/support/topic-tag/fatal/)
 * [Fatal error: Call to undefined](https://wordpress.org/support/topic-tag/fatal-error-call-to-undefined/)

 * In: [Fixing WordPress](https://wordpress.org/support/forum/how-to-and-troubleshooting/)
 * 5 replies
 * 2 participants
 * Last reply from: [jenmorrison](https://wordpress.org/support/users/jenmorrison/)
 * Last activity: [16 years, 10 months ago](https://wordpress.org/support/topic/fatal-error-message-12/#post-1179195)
 * Status: resolved

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