If you change the password on your MSN, AIM, or Yahoo account after you've imported the contacts from those accounts into Gizmo5, you will have to re-register those accounts with Gizmo5 using your new login.
After you have unregistered, in Gizmo5 go to "Contacts >> Find Friends" and follow the instructions.
See also:Â "How do I unregister my network account from Gizmo5?"