Fatal error trying to access to nav-menu.php

This may be a plugin or theme conflict. Please attempt to disable all plugins, and switch to the default Twenty Nineteen theme. If the problem goes away, enable them one by one to identify the source of the problem.

If you can install plugins, install Health Check. On the troubleshooting tab, you can click the button to disable all plugins and change the theme for you, while you’re still logged in, without affecting normal visitors to your site.

Even disabling all plugins and switching to default theme, I got some fatal errors:

Fatal error: Allowed memory size of 1073741824 bytes exhausted (tried to allocate 20480 bytes) in /home/studyaustralia/public_html/wp-includes/wp-db.php on line 1972

Fatal error: Allowed memory size of 1073741824 bytes exhausted (tried to allocate 20480 bytes) in /home/studyaustralia/public_html/wp-includes/class-wp-fatal-error-handler.php on line 65

Ok, here are three ways to increase PHP’s memory allocation:

1. If you can edit or override the system php.ini file, increase the memory limit. For example, memory_limit = 128M

2. If you cannot edit or override the system php.ini file, add php_value memory_limit 128M to your .htaccess file.

3. If neither of these work, it’s time to ask your hosting provider to temporarily increase PHP’s memory allocation on your account. Keep in mind that most decent hosting providers allow users to temporarily increase the memory allocation. If your hosting provider won’t accommodate you, perhaps it’s time to find a new hosting provider. We have some recommendations at https://www.ads-software.com/hosting/

(in the above examples, the limit is set to 128MB)

Searching for more info from info.php, I found this:

memory_limit 1024M 1024M

First number is LocalValue and the second one is MasterValue.

Has PHP already the memory limit I need?

Hm, it may be the other way around then, that you’re trying to allocate more memory than is available.

What type of server are you on (shared, VPS, or dedicated), and how much RAM does it have?

I think it’s a shared server.

Ok, then you’re definitely probably requesting more RAM than the server has available at the time. ??

Try 128M or 256M .