The passwords tab changes values for the PHONE password only… these settings have no bearing on the NT password behavior.
User cannot change password. Set this drop down to “true” to prevent the subscriber from changing the phone password via the phone interface (they can still change it by accessing the AA if you have them configured to allow it).
User must change password at next login. Set this drop down to “true” to force the selected subscribers to change their phone password the first time they log into their mailbox over the phone.
Password never expires. Set this value to “true” to allow subscribers to use the same phone password indefinitely regardless of what the system wide password policy dictates for password expiration time. If this value is set to “false” instead the password expiration time set on the password policy page in the SA will dictate how many time the subscribers have to change their phone password.
Skip password entry when subscriber calls from a known extension. (Unity 4.1 and later only). This option lets users log directly into their mailbox if they are calling from their work phone or any phone setup as the primary or an alternate extension on their subscriber account.
Force phone password to be: Check this box and provide a number (up to 10 digits) that will be applied to all the selected subscribers as their new phone password. If you check the box and leave the value blank, all the phone passwords for the selected subscribers will be disabled. USE WITH CAUTION.