Visual Editor Stopped Working

try a few basic troubleshooting steps:
– Flushing any caching plugins you might be running, as well as server and/or browser caches.
– deactivating 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).
– If that does not resolve the issue, try switching to the unedited default Twenty Fifteen Theme for a moment using the WP dashboard to rule out any theme-specific issue (theme functions can interfere like plugins).
– If that does not resolve the issue, try resetting the plugins foldervia FTP or SFTP or whatever file management application your host provides. Sometimes, an apparently inactive plugin can still cause problems.
– If all the above steps do not resolve the issue, then try MANUAL updating. Download a fresh copy of the WordPress .zip file to your computer, unzip it, and use that to copy up all files and folders EXCEPT the wp-config.php file and the /wp-content/ directory. You may need to delete the old copies of files & folder on your server before uploading the new ones. Read the Manual Update directions first.
– If you haven’t already done, always backup everything (including your database) before doing any actions, just in case something really goes wrong.

After working on this problem all day, I finally asked for help from my web host, SiteGround, and they fixed it in an hour. Here’s what their support team wrote once they’d got it working again…

I managed to recreate the issue on my end and and found out that it was caused by the fact that access to the following PHP script was being denied:

wp-includes/js/tinymce/wp-tinymce.php

I managed to resolve the issue by removing the code blocking access to the php file in question in the .htaccess file located in the wp-includes directory.

Your visual editor is now working as expected on my end.

And it is. Hope that helps someone.

BINGO Maxxdog!

I really appreciate all your suggestions, they were all good. But I thought I’d start with the easiest, least disruptive first – which was Maxxdog’s suggestion about looking at the .htaccess file.

I’m not sure what the code was in there that was stopping tinymce – but I tried first deleting all the content of the file – and suddenly it all started working fine!

Then I pasted the content back into the file and saved it, and nothing worked. Visual nor Text editing. So removed the content again and saved it and it all worked again.

I’m not sure what part of this .htaccess code was causing the problem, but I thought I’d paste it here and see if anyone can spot the problem.

<Files wp-tinymce.php>
allow from all
</Files>
<Files ms-files.php>
allow from all
</Files>
<FilesMatch “\.(?i:php)$”>
<IfModule !mod_authz_core.c>
Order allow,deny
Deny from all
</IfModule>
<IfModule mod_authz_core.c>
Require all denied
</IfModule>
</FilesMatch>
<Files wp-tinymce.php>
Allow from all
</Files>
<Files ms-files.php>
Allow from all
</Files>

Everything is allowed there except these two things:

<IfModule !mod_authz_core.c>
Order allow,deny
Deny from all
</IfModule>
<IfModule mod_authz_core.c>
Require all denied

But I have no idea what mod_authz_core.c is.

Apparently it’s safe to just remove the wp-includes/.htaccess file. I checked on a couple of my other WordPress sites where everything is working fine and they didn’t even have an .htaccess file in wp-includes. So I’m just going to leave it off for now unless anyone knows of a reason to keep it.

Glad that helped Jon!