Hmmmm, then this could be one of those doctor jokes... You know, 'it hurts when I lift up my arm like this...'
All joking aside, try running SGMon (in Symantec\Backup Exec) right before you are about to browse that selection and turn on all the checkboxes. Also, can you describe exactly which part of the selection browse window you are expanding within? And what does the text view of the pre-existing selection show? Is it possible the credentials you are using to browse are different that the credentials already setup for the pre-existing selection?