Open Microscopy Environment

I set up omero 4.1.1 and create some testuser in oder to test ldap authentication
Now I don't need them anymore but unfortunately an error occurred when hitting the delete button right next to the user.
You attached a screenshot of the error.html
Has anyone an idea what's wrong?

Deleting users who have logged in and created sessions is not supported at present. Basically once the user has some history he/she cannot be removed from the system. You can get around this in a few ways including:

• Changing the user's username and setting them inactive (least invasive)
• Resorting to PostgreSQL kung-fu on your own (partially invasive)
• Dropping your database (most invasive)

In Beta4.2.0, as part of the permissions changes, deletion of a user will be possible via WebAdmin.

Ah Okay thanks