Administrative Account is invalid

I have successfully installed and configured the Password 
    Expiration web part but the UI is displaying an error: 

    CheckPasswordExpiration:
    Bamboo.DirectoryServices.AdministrativeAccountException:
    Administrative Account is invalid at Bamboo.DirectoryServices.
    PasswordExpirationService...

    

CAUSE

    This error is caused when the administrative account configured 
    under the Active Directory Settings in the web part tool pane 
    does not have sufficient access to Active Directory or the incorrect
    password has been inputted.

    

RESOLUTION

    Please ensure that the administrative account has, at minimum,  
    read access to the Active Directory DB and/or that the password
    is correct.