msn user: how can i delete an user

[bart]

When i want to open msn explorer, i have to sign in first. There are 3
diffferrent users (different msn e-mail adress) to sign in with, bu I only
use one, the other are no more accesseble.

How can I delete those unused users and their icon, so when I open msn
explorer, only one user-icon is on the screen, the one who still works?

Thanks

Bart