If you just updated WordPress to the latest version or updated one of the WordPress themes or plugins on your site, then sometimes you may start to see this error while navigating inside WordPress admin panel: You do not have sufficient permissions to access this page.
There can be several reasons for this error message in WordPress admin panel. One reason can be this: You opened the options page of one of the WordPress themes or plugins on your site. Then you deactivated that theme or plugin and you refreshed that page. You will immediately get the error, You do not have sufficient permissions to access this page, because that page doesn’t exist any more.
If this isn’t the case, then try to repair your WordPress database once. If you have one of the WordPress database backup plugins installed on your site, then check its options and you might see an option to repair the database.
If you don’t have any active WordPress backup plugin, then you can manually repair WordPress database. To do that login to your web hosting control panel and then go to phpmyadmin and then repair database. If you have never used phpmyadmin before, then first learn how to repair WordPress database from phpmyadmin.
Repairing WordPress database will resolve this issue. If even this doesn’t work and you still keep getting the same error, then try disabling all your active plugins once and switch to default WordPress theme. If this fixes the issue, then one of the themes or plugins might be incompatible with the WordPress version you have.
To find out the incompatible theme or plugin, activate them one by one and check when you start getting the error, You do not have sufficient permissions to access this page, again.
If all else fails, you might have to hire a WordPress developer to fix this for you.