Sub panel neutral bar not testing isolated

[jaggedben]

At one time it was permitted. How old was the installation?

I don't think it was ever permitted not to bond the metal enclosure of a panelboard? These were probably done 60s or later, definitely a violation when installed.

Actually now that I'm thinking, I can picture at least two that were clearly replacements in the last 30 years, where they reused the old cable. No excuse really.