ISP Password

In internet options my ISP username is correct but the password is not the one relevent to the ISP (there is just a series of 16 dots and It is not a password inserted by me).
I am unable to change this password to the correct one because it always reverts back to the 16 dots.
It does not affect my ISP connection but but my Norton live update will not automatically update without the correct pasword in place.
Can you please help me to rectify this problem.

Regards

David Owen