We investigated this issue earlier this week, and it appears that the problem is on Norton Password Manager's side. We have communicated the issue to them, and they are currently investigating the issue.
Currently, we suggest working around the problem by temporarily disabling the Norton extension, signing into SmarterMail with "Remember Me" enabled", then re-enabling the extension. As long as you don't log out of SmarterMail, this will bypass the problem.
Andrew Barker
Software Developer
SmarterTools Inc.
www.smartertools.com