title: ERROR 1396 (HY000): Operation CREATE USER failed for 'jack'@'localhost'
body: <p>I seem to be unable to re-create a simple user I've deleted, even as root in MySQL.</p>
  
  <p>My case: user 'jack' existed before, but I deleted it from mysql.user in order to recreate it. I see no vestiges of this in that table. If I execute this command for some other, random username, say 'jimmy', it works fine (just as it originally did for 'jack').</p>
  
  <p>What have I done to corrupt user 'jack' and how can I undo that corruption in order to re-create 'jack' as a valid user for this installation of MySQL?</p>
  
  <p>See example below. (Of course, originally, there was much time between the creation of 'jack' and his removal.)</p>
  
  <pre><code>mysql&gt; CREATE USER 'jack'@'localhost' IDENTIFIED BY 'test123';
  Query OK, 0 rows affected (0.00 sec)
  
  mysql&gt; select user,host from user;
  +------------------+-----------------+
  | user             | host            |
  +------------------+-----------------+
  | root             | 127.0.0.1       |
  | debian-sys-maint | localhost       |
  | jack             | localhost       |
  | root             | localhost       |
  | root             | russ-elite-book |
  +------------------+-----------------+
  5 rows in set (0.00 sec)
  
  mysql&gt; delete from user where user = 'jack';
  Query OK, 1 row affected (0.00 sec)
  
  mysql&gt; select user,host from user;
  +------------------+-----------------+
  | user             | host            |
  +------------------+-----------------+
  | root             | 127.0.0.1       |
  | debian-sys-maint | localhost       |
  | root             | localhost       |
  | root             | russ-elite-book |
  +------------------+-----------------+
  4 rows in set (0.00 sec)
  
  mysql&gt; CREATE USER 'jack'@'localhost' IDENTIFIED BY 'test123';
  ERROR 1396 (HY000): Operation CREATE USER failed for 'jack'@'localhost'
  mysql&gt; CREATE USER 'jimmy'@'localhost' IDENTIFIED BY 'test123';
  Query OK, 0 rows affected (0.00 sec)
  
  mysql&gt; select user,host from user;
  +------------------+-----------------+
  | user             | host            |
  +------------------+-----------------+
  | root             | 127.0.0.1       |
  | debian-sys-maint | localhost       |
  | jimmy            | localhost       |
  | root             | localhost       |
  | root             | russ-elite-book |
  +------------------+-----------------+
  5 rows in set (0.00 sec)
  </code></pre>