Ever since the latest version of Norton was updated last month (7/2015) - the Norton vault will say Vault not open, I have to exit chrome and back in again, sometimes twice to get it back.
Sometimes it says not open for about 4-5 seconds while sitting on login page then flip to Open.
I have latest version on Norton Internet Security (22.5.2.15) and the extensions for Chrome 2015.5.0.121 & NIS 1.0.5