So you try and delete a user in Active directory and get a message asking if you are sure you want to delete it and all of the objects it contains.
You stop and think, what objects does it contain?
This is normally caused by old Exchange 2010 attributes attached to the user account. To see what the sub objects are click on ‘View’ then ‘Users, Contacts, Groups and Computers as containers.’ from within Active directory users and computers.
now you should see a triangle symbol next to the user account. Click on it to expand the contents and view the objects. Here we can see some old Active sync device information left over from an old Exchange server installation.
You can safely delete the user and all child objects.