This error has the following cause and solution:
Re-enter the password. Because it does not appear on the screen, it is very easy to type it incorrectly. Note that the VSS password is case-insensitive. If you believe you have typed the password correctly and VSS doesn't recognize it, ask your VSS Administrator to change your username and password. If you have forgotten your password, the VSS Administrator can use Administrator to assign you a new one.