NT FTP woes

I am running NT4 sp6 on my server. I have a webpage running, no prob, an FTP server running, no prob. The problem comes when i am now trying to add user accounts to the ftp server. I go to the Inet services manager, and it says there are errors loading W3scfg.dll and fscfg.dll. Then it says there are no administerable services available, which is patently absurd, since the webserver and exchange server, plus ftp are running fine.
What is the prob, and can you tell me how to add user accounts to the ftp server?