Mac on a Windows 2000 network

I am not really sure if this is an obvious question or not, but I want to connect my mac to the office’s WIN2K network and read my email. I can connect to the network without a problem, but when I try to set up Outlook 2000 on my mac I am not sure what to do. Connecting to the network, I am not prompted for a password. Could that be the problem? Any ideas would help.