Just upgraded ubuntu and checked my all config is as it is. All was ok then i started my phpmyadmin and found error:
Solution is as easy as changing one line in a configuration file.
We’ll set the AllowNoPassword variable, located in phpMyAdmin’s configuration file, to TRUE.
Go to /etc/phpmyadmin/config.inc.php and open it in your favorite editor.
Search for below line of code:
//$cfg['Servers'][$i]['AllowNoPassword'] = TRUE;
And uncomment the //$cfg[‘Servers’][$i][‘AllowNoPassword’] = TRUE; (just remove “//” from start) to make login in phpmyadmin with password
There are two instances of this line in the configuration file be SURE to uncomment both of them!
Save your file and try to login your phpmyadmin without password. If you still have issue try to restart your Apache services by following command:
service apache2 restart
You are done, error should be fixed now.