We have changed the user name of an account on an SBS 2003 server (from Tim to Emma). We have changed the name in ADUC in all places I could find. All functions are fine including e-mail and security but when that person has a file open and someone else tried to open the file, we get a message - "file in use ..... XXX is locked for edting by Tim (the original account name). I can't find anywhere that still references the original username Tim but it must exist in the deep memory of AD. Any ideas on how to change this.