The default password for 'root user is EMPTY (nothing). But the MySQL server may have been set up and configured with some script or application defining a password.
If you have lost access to your MySQL server you are close to getting it right. You will have to start MySQL with the –skip-grants-table option. Now you can define details for root (and any user). Next start the server normally.
Full details in MySQL documentation here: http://dev.mysql.com…ermissions.html