Title: Warning function array – advice please!
Last modified: August 21, 2016

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# Warning function array – advice please!

 *  [thehels](https://wordpress.org/support/users/thehels/)
 * (@thehels)
 * [12 years, 7 months ago](https://wordpress.org/support/topic/warning-function-array-advice-please/)
 * Hello, I tried auto-updating wordpress on my site to 3.6 last night and it took
   a very long time and didn’t complete. It prompted me to keep trying the auto-
   update, so I tried a few more times to update, then resorted to a manual update
   when that didn’t work. I followed the instructions to the letter [here](http://codex.wordpress.org/Upgrading_WordPress#Manual_Update),
   but I now have the following in the header of every page on my site:
 * Warning: call_user_func_array() [function.call-user-func-array]: First argument
   is expected to be a valid callback, ‘_show_post_preview’ was given in /mydomainname.
   co.uk/public_html/wp-includes/plugin.php on line 406
 * When I try to access the wp-admin page I just get a screen with the same text
   above, followed by
 * Warning: Cannot modify header information – headers already sent by (output started
   at /mydomainname.co.uk/public_html/wp-includes/plugin.php:406) in /mydomainname.
   co.uk/public_html/wp-includes/pluggable.php on line 875
 * As I can’t get into the wp-admin panel to do anything (i.e. try it with a different
   theme), I have tried disabling the plugins one by one by removing them via FTP(
   I first tried renaming the plugins folder to plugins.hold – but this made no 
   difference). I have also tried replacing the wordpress files again (as per the
   upgrade).
 * I have read a number of other posts on this issue but I don’t think any of them
   apply to me as I don’t have any of the plugins mentioned.
 * I am not at all experienced in php and am at a loss here as to what to do. Any
   help would be much appreciated!
 * Many thanks.

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

 *  [esmi](https://wordpress.org/support/users/esmi/)
 * (@esmi)
 * [12 years, 7 months ago](https://wordpress.org/support/topic/warning-function-array-advice-please/#post-4034713)
 * Try:
    – switching to the default theme by renaming your current theme’s folder
   inside wp-content/themes and adding “-old” to the end of the folder name using
   [FTP](http://codex.wordpress.org/FTP_Clients) or whatever file management application
   your host provides.
 * – [resetting the plugins folder](http://codex.wordpress.org/FAQ_Troubleshooting#How_to_deactivate_all_plugins_when_not_able_to_access_the_administrative_menus.3F)
   by FTP or phpMyAdmin.
 * – re-uploading all files & folders – **except** the wp-content folder – from 
   a **fresh** download of WordPress. Make sure that you delete the old copies of
   files & folder before uploading the new ones.
 * – running the upgrade manually via wp-admin/upgrade.php
 *  [kulwant2sin](https://wordpress.org/support/users/kulwant2sin/)
 * (@kulwant2sin)
 * [12 years, 7 months ago](https://wordpress.org/support/topic/warning-function-array-advice-please/#post-4034724)
 * Replace the functions.php file of your theme by downloading original file for
   that theme . Or re install your theme if you have child theme .
 *  Thread Starter [thehels](https://wordpress.org/support/users/thehels/)
 * (@thehels)
 * [12 years, 7 months ago](https://wordpress.org/support/topic/warning-function-array-advice-please/#post-4034797)
 * Thank you esmi and kulwant2sin for your speedy replies. I tried all the suggestions
   you gave – the one that finally worked was reuploading everything from a fresh
   wp download. I’m so grateful that it’s all working now – thanks for your help.
 * Now it’s working properly again I thought it was time to do a bit of housekeeping,
   so I decided to update all my plugins/themes as I think this is where my problems
   began. I updated them one by one but the process was incredibly slow – could 
   this be linked to the same issue?
 * Thanks again for your help.

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

The topic ‘Warning function array – advice please!’ is closed to new replies.

## Tags

 * [array](https://wordpress.org/support/topic-tag/array/)
 * [function](https://wordpress.org/support/topic-tag/function/)
 * [valid callback](https://wordpress.org/support/topic-tag/valid-callback/)
 * [warning](https://wordpress.org/support/topic-tag/warning/)

 * In: [Fixing WordPress](https://wordpress.org/support/forum/how-to-and-troubleshooting/)
 * 3 replies
 * 3 participants
 * Last reply from: [thehels](https://wordpress.org/support/users/thehels/)
 * Last activity: [12 years, 7 months ago](https://wordpress.org/support/topic/warning-function-array-advice-please/#post-4034797)
 * Status: not resolved

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