PhpMyAdmin login failed

If a customer complains that he is unable to log into phpMyAdmin from his cPanel and getting phpmyadmin login window or login failed error, first check and see if it is a server wide issue. If it is a server wide issue force upgrading phpMyAdmin will fix the issue. For that,

SSH to your server as root and update phpmyadmin :

#/usr/local/cpanel/bin/updatephpmyadmin --force
If the issue is only for one user, do the following

1) Log into WHM and go to  Account Functions »Password Modification
2) Select user account and update password with the same as current one

Note : While updating password for user make sure "Allow MySQL password change" option is checked.

Any queries, please let me know..