At seemingly random intervals, a user without configure list rights manages to delete and recreate the default list for the task table, effectively changing the list display for all users in the system.

1. Open existing list views as an administrator.
2. Locate any GLOBAL list view with Default view and blank user - delete it.
3. Impersonate an ITIL user.
4. Navigate to My work. 
   Note that there is no Default GLOBAL View.
5. Go back to an admin account.
6. Open list views. 
   Note the GLOBAL Default View created for the previous non-admin user.
7. Delete this list view again.
8. Impersonate another user.
9. Navigate to My Work.
   Note that there is no Default GLOBAL View. 
10. Repeat steps 5-6.
    Note that these new views have different sets of columns than the base system Default view.

This problem has been split into the following:

- PRB659934 - Fixed since Geneva Patch 8 - List view personalizations actually being deleted - Running a public report against the table by an unauthenticated user cases the default view for that table to be deleted

- PRB650566 - Fixed since Geneva Patch 4 - in Normal lists are cached based on the combination of role so users with the same role combination will see the sysform_realcache entry for that matching set of roles

- PRB570571 - Fixed since Helsinki - Embedded lists are cached based on the combination of role so users with the same role combination will see the sysform_realcache entry for that matching set of roles

As a partial workaround, and to avoid manually fixing the list when the problem occurs, follow these steps:

1. Export the sys_ui_list record after you have fixed it the first time.
2. Re-import it if the problem appears again (overwriting the corrupt one).