I had similar error during `CREATE USER` query.

I did following solution to rectify the user table.

	ALTER TABLE `user` ADD `Create_tablespace_priv` ENUM('N','Y') NOT NULL DEFAULT 'N' AFTER `Trigger_priv`; 
	ALTER TABLE `user` ADD `plugin` CHAR(64) NULL AFTER `max_user_connections`; 
	ALTER TABLE `user` ADD `authentication_string` TEXT NULL DEFAULT NULL AFTER `plugin`; 
	ALTER TABLE `user` ADD `password_expired` ENUM('N','Y') NOT NULL DEFAULT 'N' AFTER `authentication_string`; 

Now `CREATE USER` query works fine.!!

Rectification is achieved from the reference of the answer to [Cannot GRANT privileges as root](http://dba.stackexchange.com/questions/16397/cannot-grant-privileges-as-root/16441#16441).
Thank you [RolandoMySQLDBA](http://dba.stackexchange.com/users/877).!

Following helped to create above SQL:
<PRE>
+------------------------+------------------------+-----------------------------------+------+-----+---------+
| Field (MySQL 5.1)      | Field (MySQL 5.6)      | Type                              | Null | Key | Default |
+------------------------+------------------------+-----------------------------------+------+-----+---------+
| Host                   | Host                   | char(60)                          | NO   | PRI |         |
| User                   | User                   | char(16)                          | NO   | PRI |         |
| Password               | Password               | char(41)                          | NO   |     |         |
| Select_priv            | Select_priv            | enum('N','Y')                     | NO   |     | N       |
| Insert_priv            | Insert_priv            | enum('N','Y')                     | NO   |     | N       |
| Update_priv            | Update_priv            | enum('N','Y')                     | NO   |     | N       |
| Delete_priv            | Delete_priv            | enum('N','Y')                     | NO   |     | N       |
| Create_priv            | Create_priv            | enum('N','Y')                     | NO   |     | N       |
| Drop_priv              | Drop_priv              | enum('N','Y')                     | NO   |     | N       |
| Reload_priv            | Reload_priv            | enum('N','Y')                     | NO   |     | N       |
| Shutdown_priv          | Shutdown_priv          | enum('N','Y')                     | NO   |     | N       |
| Process_priv           | Process_priv           | enum('N','Y')                     | NO   |     | N       |
| File_priv              | File_priv              | enum('N','Y')                     | NO   |     | N       |
| Grant_priv             | Grant_priv             | enum('N','Y')                     | NO   |     | N       |
| References_priv        | References_priv        | enum('N','Y')                     | NO   |     | N       |
| Index_priv             | Index_priv             | enum('N','Y')                     | NO   |     | N       |
| Alter_priv             | Alter_priv             | enum('N','Y')                     | NO   |     | N       |
| Show_db_priv           | Show_db_priv           | enum('N','Y')                     | NO   |     | N       |
| Super_priv             | Super_priv             | enum('N','Y')                     | NO   |     | N       |
| Create_tmp_table_priv  | Create_tmp_table_priv  | enum('N','Y')                     | NO   |     | N       |
| Lock_tables_priv       | Lock_tables_priv       | enum('N','Y')                     | NO   |     | N       |
| Execute_priv           | Execute_priv           | enum('N','Y')                     | NO   |     | N       |
| Repl_slave_priv        | Repl_slave_priv        | enum('N','Y')                     | NO   |     | N       |
| Repl_client_priv       | Repl_client_priv       | enum('N','Y')                     | NO   |     | N       |
| Create_view_priv       | Create_view_priv       | enum('N','Y')                     | NO   |     | N       |
| Show_view_priv         | Show_view_priv         | enum('N','Y')                     | NO   |     | N       |
| Create_routine_priv    | Create_routine_priv    | enum('N','Y')                     | NO   |     | N       |
| Alter_routine_priv     | Alter_routine_priv     | enum('N','Y')                     | NO   |     | N       |
| Create_user_priv       | Create_user_priv       | enum('N','Y')                     | NO   |     | N       |
| Event_priv             | Event_priv             | enum('N','Y')                     | NO   |     | N       |
| Trigger_priv           | Trigger_priv           | enum('N','Y')                     | NO   |     | N       |
<b>|                        | Create_tablespace_priv | enum('N','Y')                     | NO   |     | N       |</B>
| ssl_type               | ssl_type               | enum('','ANY','X509','SPECIFIED') | NO   |     |         |
| ssl_cipher             | ssl_cipher             | blob                              | NO   |     | NULL    |
| x509_issuer            | x509_issuer            | blob                              | NO   |     | NULL    |
| x509_subject           | x509_subject           | blob                              | NO   |     | NULL    |
| max_questions          | max_questions          | int(11) unsigned                  | NO   |     | 0       |
| max_updates            | max_updates            | int(11) unsigned                  | NO   |     | 0       |
| max_connections        | max_connections        | int(11) unsigned                  | NO   |     | 0       |
| max_user_connections   | max_user_connections   | int(11) unsigned                  | NO   |     | 0       |
<b>|                        | plugin                 | char(64)                          | YES  |     |         |</B>
<b>|                        | authentication_string  | text                              | YES  |     | NULL    |</B>
<b>|                        | password_expired       | enum('N','Y')                     | NO   |     | N       |</B>
+------------------------+------------------------+-----------------------------------+------+-----+---------+
</PRE>