Originally Posted by till
Most likely the mysql root password has been changed in mysql without changing it in ispconfig so that ispconfig is not able to alter the mysql user. Check that the mysql root password is correct in the file /usr/local/ispconfig/server/lib/mysql_clientdb.conf
I just checked the root password in the mysql_clientdb.conf with "mysql -u root -p" and it logged in fine. I haven't changed the mysql root password since installing ispconfig.