Why does "Cancel People Account" not work?

I have Drupal 7 with Devel installed running over PHP internal server and MySQL.All user operations work correctly except Admin>People>Cancel Account operation.

This leads to the overlay Add User and a Cancel Accounts button.If I select the option: Delete the account and its content and press Cancel Accounts.

This leaves the overlay(displays the home page of the user)

All I want at this point is to be in the backend Overlay and show the message Changes saved or something similar.When I return to Admin People overlay, the user is still there.

Has anyone experienced a similar problem - and do you have a solution?

Thank You.-Robert.