One of our users complained about not being able to login anymore. He had some issues logging in since about a week he told me. Of course, when I stood next to him the logon process worked fine, but he had lost all his tasks and profile picture.
Now, when I search for his username using the search-field at the top of the screen, I see a user called "Unknown User (u.sername)" (offcourse not really u.sername but his true username 
). When I seek his full name I see his full name as a user. When I click either one of them, I get the same profile page of user "u.sername". Confluence tells me that this account was created Mar 30, 2015 12:27, about a week ago.
We didn't made any configuration changes on that date... we did update confluence to the latest version but have done so a week before that date. Nothing was wrong with his account after the upgrade.
In the database I see that this user has two user_key's:
mysql> select * from user_mapping where username='u.sername';
+----------------------------------+-------------+----------------+
| user_key | username | lower_username |
+----------------------------------+-------------+----------------+
| xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx | u.sername | u.sername |
| yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy | u.sername | NULL |
+----------------------------------+-------------+----------------+
2 rows in set (0.00 sec)
We use atlassian crowd to login to confluence through a local JIRA instance, which on its turn uses Active Directory for authentication. Nothing was changed on both JIRA and our AD at this date as well.
I see that Confluence did a userdir-sync exactly at the time the user was 'created', in the log it says:
2015-03-30 12:27:58,322 INFO [scheduler_Worker-2] [atlassian.crowd.directory.DbCachingRemoteChangeOperations] addUsers adding [ 1 ] users
In the JIRA log however, no changes for the userdir are mentioned.
Could someone point us in a direction on how this could have happened and is it possible to merge both 'user_keys' so this user gets his tasks back?
