Unable to delete users


After adding users on lifetime, If i want to delete any user, its throwing me the below error message. May i know the reason for below message? Also please help me on resolving this. 

Hi Shwetha.

For the personal environment I just know you can get users inactivated. You can't delete it.

Inactive users are not counted on licensing, so I think this could help you.


Luciano Guimaraes