ERROR Updating failed. Error message: The response is not a valid JSON response.

I also got this error. I have built a website on my Raspberry Pi to learn and have fixed many errors for this.
To solve this error:
Step 1: enable rewrite module

$ sudo a2enmod rewrite
$ systemctl restart apache2

Step 2: modify apache site configuration
$ sudo nano /etc/apache2/sites-available/000-default.conf

add some directives like below:

<VirtualHost *:80>
    ServerName example.com
    ServerAlias www.example.com
    
    RewriteEngine on
    RewriteCond %{SERVER_NAME} =example.com [OR]
    RewriteCond %{SERVER_NAME} =www.example.com
    RewriteRule ^ http://%{SERVER_NAME}%{REQUEST_URI} [END,NE,R=permanent]
    
    <directory /var/www/html>
        Options Indexes FollowSymLinks MultiViews
        AllowOverride All
        Require all granted
    </directory>

    ServerAdmin webmaster@localhost
    DocumentRoot /var/www/html
    ErrorLog ${APACHE_LOG_DIR}/error.log
    CustomLog ${APACHE_LOG_DIR}/access.log combined
</VirtualHost>

Restart Apache
$ systemctl restart apache2

I read from this post Removing Index.php From the URL Slug in WordPress

• This reply was modified 3 years, 4 months ago by talucgiahoang.
• This reply was modified 3 years, 4 months ago by talucgiahoang.
• This reply was modified 3 years, 4 months ago by talucgiahoang.

We have the issue on sites behind AWS Loadbalancers.

for example, two of our sites use Cloudflare -> AWS ELB -> EC2, when taking AWS ELB out and pointing Cloudflares DNS directly to a single EC2 instance the error goes away.

The same sites also have the same Gutenberg issues on Localhost if we run them within docker environments.

• This reply was modified 3 years, 4 months ago by brand42. Reason: Adding the same issue but for docker

Hello @macmanx,

I am facing the issue of “the response is not a valid JSON response.”

When I was updating Shortcode in block editor I was getting this error, I tried multiple scenarios even by updating Perma Links but it didn’t worked.
Later I used Classic Editor WordPress.org plugin and tried to update the shortcode it was functioning smoothly as expected and no errors while saving the page.

i just started a new theme Otography. i realize this is a wordpress issue not theme issue. this is the first time in months i’ve had to work on my websites and now i’m experiencing this issue.

i’ve made the settings adjustment as suggested – no luck.

i’ve deactivated any possible plugins (beaver builder) since this WP version seems to have its own blocks. – no luck.

help?

and no, i’m not a web designer. just a photographer and educator needing to maintain his own websites.

help appreciated.

Me again – yes seems to have something to do with the Title field. It doesn’t save it when I select “save draft”…and doesn’t allow me to input anything that it likes.

@mhollimc Hi, not sure if this will help, honestly, as i’m not a WP nerd…just a photographer who does his own sites.

I was also using BB and had built out two sites using it. The majority of the work had to be rebuilt from scratch using the new WP Gutenberg method of blocks. Some of the blocks could be converted. Some could not.

I have been told BB works with this new WP setup…but I have not had luck and get the same warning. I’ve given in to the WP Gutenberg blocks. They’re pretty limited compared to BB from what I can tell.

I’ve been assimilated.

[ Signature deleted ]

• This reply was modified 1 year, 8 months ago by Jan Dembowski.