Failed to install mysql on ubuntu 14.04

I cannot install mysql on ubuntu 14.04, I tried to install various times but failed. I searched to completely uninstall mysql and reinstall it again, I tried but couldn't install. This always gives me the error unable to set a password for the root user.

Unable to set password for the Mysql "root" user

An error occurred while setting password for the mysql
administrative user.This may have happened because the account already has a password, or because of a communication problem with the Mysql server.
You should check the account password after the package installation.
Please read the /usr/share/doc/mysql-server-5.5/README.Debian file for more information.

      

        
        
        
      

    

I am searching but not successful

thanks for the help