Solution 1:
The easiest way to fix this issue is to create a fresh WordPress installation.
⚠️ Since the problem could happen again, it’s highly recommended to regularly back up your site, including:
Database
WordPress export
wp-content folder or the entire public_html directory
Regular backups ensure quick recovery if similar issues arise in the future.
Solution 2:
I resolved my site issues today by checking the error log. Many errors looked like:
Duplicate entry ‘0’ for key ‘PRIMARY’…
This indicates that some database tables were missing the AUTO_INCREMENT property on their primary key fields.
✅ How to fix it:
Identify the affected tables from the error log.
Modify the table structure to add AUTO_INCREMENT to the primary key column.
Once the primary keys have AUTO_INCREMENT, the duplicate entry errors should be resolved.