Dial-Up Networking won't remember your PasswordBy: Arie Slob
In some cases, Dial-Up Networking will not remember passwords. What happens is that either the Save Password check box is disabled, or the setting is ignored.
To fix this problem, see one of these Microsoft's Knowledge Base articles:
In some cases, the Password List files get corrupted. Try deleting (make a backup prior to deleting) all .PWL files in your \Windows directory, then try to connect again and save your password.
Your *.pwl file(s) contain your passwords.
If all else fails, try re-creating the Dial-Up Networking connection.