Plesk upgrade fails: Query failed: ALTER TABLE `pd_users` MODIFY COLUMN `login` varchar(32) NOT NULL

As a workaround, delete one of the users:

1. Connect to the server via SSH.

2. Use the number from the duplicate entry reported in the error message to find the entries. In the example symptom, it is 50-johndoe:

   MYSQL_LIN: mysql> select * from pd_users WHERE pd_id=50;
   +—–+————-+————+——-+
   | id | login | account_id | pd_id |
   +—–+————-+————+——-+
   | 144 | Johndoe | 0 | 50 |
   | 145 | johndoe | 0 | 50 |

3. Find the ID of the domain the protected directory belonged to and the path to the directory itself, use the pd_id as id to search in the protected_dirs table :

   MYSQL_LIN: mysql> select * from protected_dirs where id=50;
   +—-+———+——-+———+——-+——-+——–+———-+
   | id | non_ssl | ssl | cgi_bin | realm | path | dom_id | dom_type |
   +—-+———+——-+———+——-+——-+——–+———-+
   | 50 | true | false | false | | protected-path| 41 | domain |
   +—-+———+——-+———+——-+——-+——–+———-+
   1 row in set (0.00 sec)

4. Find the domain name using the dom_id as id to search in the domains table:

   MYSQL_LIN: mysql> select name from domains where id=41;
   +——————+
   | name |
   +——————+
   | example.com |
   +——————+
   1 row in set (0.00 sec)

5. Log in to Plesk and navigate to Domains > example.com > Password-Protected Directories > /protected-path.

6. Removed the user Johndoe.