Title: Fatal error Last modified: September 23, 2016 --- # Fatal error * [makelures](https://wordpress.org/support/users/makelures/) * (@makelures) * [9 years, 7 months ago](https://wordpress.org/support/topic/fatal-error-1510/) * Getting the following error on the site [https://makewoodenlures.com/](https://makewoodenlures.com/) * Fatal error: Call to undefined function is_blog_installed() in /home/makewood/ public_html/wp-includes/load.php on line 532 * Warning: call_user_func_array() expects parameter 1 to be a valid callback, function‘ wp_ob_end_flush_all’ not found or invalid function name in /home/makewood/public_html/ wp-includes/plugin.php on line 524 * I’ve been into cpanel and tried replacing the core file load.php with a fresh version…. no luck. * Any advice? Please go easy, I’m not a coder 😉 Viewing 15 replies - 1 through 15 (of 17 total) 1 [2](https://wordpress.org/support/topic/fatal-error-1510/page/2/?output_format=md) [→](https://wordpress.org/support/topic/fatal-error-1510/page/2/?output_format=md) * Moderator [t-p](https://wordpress.org/support/users/t-p/) * (@t-p) * [9 years, 7 months ago](https://wordpress.org/support/topic/fatal-error-1510/#post-8214930) * > Warning: call_user_func_array() expects parameter 1 to be a valid callback * It sounds like you’re removing the function without removing the call to the function. In other words, it is just a call to a function that no longer exists.– Just locate that call (add_action for example) and try removing it or comment it out. * Thread Starter [makelures](https://wordpress.org/support/users/makelures/) * (@makelures) * [9 years, 7 months ago](https://wordpress.org/support/topic/fatal-error-1510/#post-8214945) * Awesome, thanks Tara. That makes sense…… but I wouldn’t have a clue where to start looking…. sorry to be such a noob! * Moderator [t-p](https://wordpress.org/support/users/t-p/) * (@t-p) * [9 years, 7 months ago](https://wordpress.org/support/topic/fatal-error-1510/#post-8214958) * Try: – deactivating ALL (yes all) plugins temporarily to see if this resolves the problem (plugin functions can interfere). If this works, re-activate them individually (one-by-one) to find the problematic plugin(s). – [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](http://codex.wordpress.org/FTP_Clients). Also remember to deactivate any plugins in the mu-plugins folder (if you have created such folder). The easiest way is to rename that folder to mu-plugins-old. – switching to the unedited default Theme (Twenty Sixteen) for a moment using the WP dashboard to rule out any theme- specific issue (theme functions can interfere like plugins). * Thread Starter [makelures](https://wordpress.org/support/users/makelures/) * (@makelures) * [9 years, 7 months ago](https://wordpress.org/support/topic/fatal-error-1510/#post-8214994) * ok, thanks Tara. I’ll give that a go. Appreciate your advice and your patience * Thread Starter [makelures](https://wordpress.org/support/users/makelures/) * (@makelures) * [9 years, 7 months ago](https://wordpress.org/support/topic/fatal-error-1510/#post-8215042) * Thanks Tara, I switched off all plugins, then went to /wp-admin/plugins.php and got the following: * W3 Total Cache Error: some files appear to be missing or out of place. Please re-install plugin or remove /home/makewood/public_html/wp-content/advanced-cache. php.W3 Total Cache Error: some files appear to be missing or out of place. Please re-install plugin or remove /home/makewood/public_html/wp-content/object-cache. php. Fatal error: Call to undefined function is_blog_installed() in /home/makewood/ public_html/wp-includes/load.php on line 532 * Warning: call_user_func_array() expects parameter 1 to be a valid callback, function‘ wp_ob_end_flush_all’ not found or invalid function name in /home/makewood/public_html/ wp-includes/plugin.php on line 524 * Thread Starter [makelures](https://wordpress.org/support/users/makelures/) * (@makelures) * [9 years, 7 months ago](https://wordpress.org/support/topic/fatal-error-1510/#post-8215073) * temporarily renaming advanced-cache and object-cache returned the original error. Appears to be a problem with W3 total cache though. * Still unable to login in to wp-admin * [kmessinger](https://wordpress.org/support/users/kmessinger/) * (@kmessinger) * [9 years, 7 months ago](https://wordpress.org/support/topic/fatal-error-1510/#post-8215240) * That error is usually a sign an auto update failed. Try downloading WordPress again and replace your copies of everything EXCEPT the wp-config.php file and the wp-content directory with fresh copies. This should replace your core files without changing your content and settings in wp-config.php file and the wp-content directory. * Thread Starter [makelures](https://wordpress.org/support/users/makelures/) * (@makelures) * [9 years, 7 months ago](https://wordpress.org/support/topic/fatal-error-1510/#post-8216364) * Thanks kmessinger * I’ve since replaced wordpress with freshly downloaded files (except wp-content and config.php). * I now get nothing at all….. just a white screen. * heeelp! * Moderator [t-p](https://wordpress.org/support/users/t-p/) * (@t-p) * [9 years, 7 months ago](https://wordpress.org/support/topic/fatal-error-1510/#post-8217395) * Have you tried [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](http://codex.wordpress.org/FTP_Clients). Also remember to deactivate any plugins in the mu-plugins folder (if you have created such folder). The easiest way is to rename that folder to mu-plugins-old. – switching to the unedited default Theme (Twenty Sixteen) for a moment using the WP dashboard to rule out any theme-specific issue (theme functions can interfere like plugins). If you don’t have access to your admin area, use [FTP ](http://codex.wordpress.org/FTP_Clients), or your web-host’s cPanel or whatever file management application your host provides( no Dashboard access required). Navigate to /wp-content/themes/ and switch to the default theme by renaming your current theme’s folder by adding “-old” to the end of the folder name. Alternately, you can remove other themes except the default theme. That will force your site to use it. * Also try reviewing this codex: [http://codex.wordpress.org/Common_WordPress_Errors#The_White_Screen_of_Death](http://codex.wordpress.org/Common_WordPress_Errors#The_White_Screen_of_Death) * Thread Starter [makelures](https://wordpress.org/support/users/makelures/) * (@makelures) * [9 years, 7 months ago](https://wordpress.org/support/topic/fatal-error-1510/#post-8217965) * Hi Tara, * Thanks for your help. Yes, I’ve disabled plugins and forced a theme change. I’ve also refreshed all wp core files except config.php amd wp-content * When I try to log in to wp-admin I get the error * Fatal error: Call to undefined function nocache_headers() in /home/makewood/public_html/ wp-admin/admin.php on line 33 * I checked out the link you gave but think I’ve done all of that…. starting to get really desperate… * Moderator [t-p](https://wordpress.org/support/users/t-p/) * (@t-p) * [9 years, 7 months ago](https://wordpress.org/support/topic/fatal-error-1510/#post-8217997) * try replacing /wp-admin/admin.php with file from a fresh download of WP * Thread Starter [makelures](https://wordpress.org/support/users/makelures/) * (@makelures) * [9 years, 7 months ago](https://wordpress.org/support/topic/fatal-error-1510/#post-8218001) * Thanks Tara, I tried that too. Unfortunately, no joy. * Moderator [t-p](https://wordpress.org/support/users/t-p/) * (@t-p) * [9 years, 7 months ago](https://wordpress.org/support/topic/fatal-error-1510/#post-8218004) * – Please check the error logs on your server for a more specific error message and see why it’s failing. If you need help locating them, ask your hosting provider to help you with that. * Thread Starter [makelures](https://wordpress.org/support/users/makelures/) * (@makelures) * [9 years, 7 months ago](https://wordpress.org/support/topic/fatal-error-1510/#post-8218039) * Thanks Tara….. just accessed APACHE error logs. It’s a blank file * Moderator [t-p](https://wordpress.org/support/users/t-p/) * (@t-p) * [9 years, 7 months ago](https://wordpress.org/support/topic/fatal-error-1510/#post-8218048) * if you don’t find any helpful info in the error logs, try [Enabling debugging ](http://codex.wordpress.org/Debugging_in_WordPress). Viewing 15 replies - 1 through 15 (of 17 total) 1 [2](https://wordpress.org/support/topic/fatal-error-1510/page/2/?output_format=md) [→](https://wordpress.org/support/topic/fatal-error-1510/page/2/?output_format=md) The topic ‘Fatal error’ is closed to new replies. ## Tags * [fatal error](https://wordpress.org/support/topic-tag/fatal-error/) * In: [Fixing WordPress](https://wordpress.org/support/forum/how-to-and-troubleshooting/) * 17 replies * 3 participants * Last reply from: [t-p](https://wordpress.org/support/users/t-p/) * Last activity: [9 years, 7 months ago](https://wordpress.org/support/topic/fatal-error-1510/page/2/#post-8218146) * Status: not resolved ## Topics ### Topics with no replies ### Non-support topics ### Resolved topics ### Unresolved topics ### All topics