The N4 setting, FRMSECURITY015 (Administration
Settings
Settings
Settings view), specifies the number of days after which a user password expires and the user needs to specify a new password. When you set this value to 0 (zero) and save, passwords do not expire for any user who subsequently logs in to that version of the N4 application.
If you upgrade to a new version of N4 you will need to reset this value as one of the first configuration tasks if you want to preserve the non-expiring passwords.