Admin permission issues

Help! I keep getting the following error:

'You do not have sufficient permissions to access this admin page.

I have checked the details in wp_users and wp_usermeta tables match those in wp-config.php. I’ve reset the wp-capabilities value to {s:13:”administrator”;s:1:”1″;}. The error still occurs.

This is a restoration of a website backup – everything seems to be okay except accessing the back-end.