Cannot retrieve user rules from database

Hi,

Where did you change the admin email: From the WordPress “Users” menu, or the “Settings” Menu or from NinjaFirewall “Event Notifications” menu?

Maybe you (or your host) had a database backup running and the tables were locked which would explain the message? Or your DB was too slow and it was not possible to connect to it?

I can change the admin password and I don’t get any error.

Did you check MySQL log?
The firewall will display the error message if this query failed:

SELECT * FROM '{table_prefix}options' WHERE 'option_name' = 'nfw_rules'

Depends on your OS, distro etc.
Folders:
/var/log/ and /var/log/mysql/
/var/lib/mysql/

Files: /var/log/messages

We can force NinjaFirewall to write the error message to the dashboard.
But fist, I need to know which message exactly you received because there are 3 differents ones.
Is it:
Cannot retrieve user rules from database (#1)
Or:
Cannot retrieve user rules from database (#2)
Or:
Cannot retrieve user rules from database (#3)

You can try this:

1. Download the /plugins/ninjafirewall/lib/firewall.php to your computer.
2. Make a backup of it (very important).
3. Open firewall.php and search for those 2 lines:
–Line 325:

define( 'NFW_STATUS', 7 );

–Line 331:

define( 'NFW_STATUS', 8 );

-Replace those 2 lines with that one:

define( 'NFW_STATUS', htmlspecialchars($nfw_['mysqli']->error) );

4. Save and upload the new version.
5. Go to your admin dashboard and paste here the error message.
6. Restore the original firewall.php backup script.