Choose Page from the Display menu. You can control the appearance of barlines and braces in the Style section of the Display Page dialog. Check Connect left side of staves in parts if you want the far left of each staff to be closed with a bar line when you are printing parts. If this option is not checked, the far left of each staff will be open when printing parts. Many editors prefer this style for orchestral parts.
You have three choices of barline styles. If you choose Join Barlines, all barlines will extend from the top of the first staff in a system to the bottom of the last staff in the system. If you choose Break Barlines by Staff, all staves in a system will have barlines, but there will be no barline connections between staves in the same system. If you choose Break Barlines by Brace Group, barlines in a system will extend across staves that are grouped together by a brace or bracket. There will be no barline connection between staves in the same system not joined by a brace or bracket.