My score has a little enclosure on the Alto 1 in the score (please see attached far left). I am trying to get rid of it. I have looked through various libraries, but am thus far unsuccessful.
Set this to never under Library->Layout Options->Staves and Systems.
Jesper
You must have created a group for only the alto. You can remove it from the group as an alternative to the above. Then you can delete the empty group with the trash can.