FTP on Domain Controller
In order for a Domain Controller, hosting IIS, to accept FTP the user must be in the Admin group. Well, unless you do this:
for FTP access to a Domain Controller that user is NOT in admin group
start/programs/admin tools/LOCAL Security policy.
Open up local policies
Open up User rights assignments
Open up Log on Locally
add your ftp user/group and put a check in the box for it.
So, if you add an Active Directory group named FTPusers then anyone you assign memebership to that AD group will then be able to FTP to the DC's FTP sites without being in the Admin group.