Join domain or standalone?

Hi everybody…

I currently have 2 server. One is DC(Win2k) and the other one is Mail server(Window server 2003).

I join the mail server to the DC domain using the particular DC admin user but all the user fail to list the mail server shared folder in my network place.

From the mail server site also fail to set permission onto that particular folder for domain user too. When i add user permission, it only show me the mail server user only

So any idea on whats going on here.