Hello, my WordPress site is showing a "Critical error on this website" message in the admin panel after uploading an incompatible theme, and I can no
Hello, my WordPress site is showing a "Critical error on this website" message in the admin panel after uploading an incompatible theme, and I can no longer access the backend. Could you please rename or delete the most recently added theme folder under /wp-content/ themes/ so that the site reverts to the default theme? Thank you!
1 Reply
That critical error message after a theme upload is almost always caused by a PHP fatal error on activation. WordPress cannot recover through the admin panel directly because the backend fails to load.
Since Linode instances are self-managed, you can fix this directly over SSH:
Connect to your server via SSH and navigate to your WordPress installation directory (for example, cd /var/www/html).
Disable the problem theme by renaming its folder:
mv wp-content/themes/your-new-theme wp-content/themes/your-new-theme-disabled
With no active theme files loaded, WordPress will automatically fall back to a default theme, allowing your site and admin panel to load again. You can then check the theme's requirements (PHP version, missing plugins) before re-enabling it.
If renaming the folder doesn't resolve the error, check your web server logs to see the exact PHP error:
Apache:
tail -n 50 /var/log/apache2/error.log
or (CentOS/RHEL)
/var/log/httpd/error_log
NGINX:
tail -n 50 /var/log/nginx/error.log
You can also check Akamai's guide for additional details: