Canon scanner won't login

Newly installed W2K3 server configured as a DC--only server on network. I
have a Canon multifunction machine which has the ability to scan from its
console to network shares. In order to do this it must "login" to my server
with a user name and password. All workstations can login to server just
fine. The scanner is set to use "Windows (SMB)" as its protocol and it can
browse to my domain and server name but when I try to drill down into the
server, the scanner prompts for a user and password. I've tried several
user/pw including administrator but the scanner will not login. If I turn on
sharing on a WXPP workstation and try logging into any of them, it works but
not to the server.
Canon says it's my server but I have no clue what to check.
Help !